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Major Corporate Social Responsibility | Principles of Management

downloadMajor Corporate Social Responsibility

Organizations have great responsibility for the welfare of the society and the environmental protection. The major corporate social responsibility are as follows:

Responsibility towards Shareholders:

Shareholders invest capital in the business and bear risks .They want return of their investment from the business.So,they have interest in the development and prosperity of their business.Therefore,the business organization has responsibility toward them as they invest money and grow business.The amin responsibilities of business towars shareholders are proper utilization of investment ,fair dividends,fair interest,providing up-to-date information of financial transactions,maximize value of investment ,allowing them to participate in planning and policy making,etc.

Responsibility toward customers:

Customer satisfaction is the ultimate goal of business organization.They are the key source of earnings.Business organization need to satisfy their customers by producing goods and services of their choice and demand .Business cannot be successful unless customers are satisfied.The responsibilities of business toward customers are providing quality products at reasonable price,adequate quantity when needed,good behaviour,avoid unfair practices like black marketing,provide after-sales service ,etc

Responsibility toward employees:                                                                                                      

The success of business largely depends on motivated employees .They are the assets of the business and their welfare and wellbeing should be the main concerned of the management. They should be treated as a part of the organization and encouraged them to produce higher productivity.They should be properly trained and provide monetary and non-monetary benefits.The main responsibilities of business toward employees is to provide meaningful job and job security,to provide fair wages and other benefits,provide welfare facilities like sports ,education,medical,etc, creating favourable working environment,conducting training and development programs.

Responsibility toward government:

All business activities should be conducted within the rules and regulations of the government Government protects and controls the activities of business.It allows business organizations to operate within certain norms.Therefore,cooperation of government is essential to business sector.The business organization must fulfill the responsibilities toward the government by  following government rules and laws,pay different taxes such as VAT,income tax,custom duty ,etc,avoid monopoly and unfair trade practices,support national problems such as unemployment and poverty ,etc.

Responsibility toward Society or Community:

Business Organizations perform their business activities in the society. Their success also depends on wellbeing of the whole society.Therefore,business organizations have some responsibilities toward society or community.They are to create employment opportunities to the people,to maintain environmental ecology,proper utilization of society’s resoures,to promote the program of community welfare services,to maintain the social and cultural values etc.

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Source Documents

Source Documents:

A piece of paper that is used as evidence to record a transactions.A source document, often called business paper, is the document produced with each business event and used to record every business transaction. In other words, it’s a physical or electronic document that lists the details of a transaction and is used by the accounting department tojournalize accounting information.

Some common examples of source documents include sales receipts,checks, purchase orders, invoices,bank statements, and payroll reports. These are all original documents that were created from a transaction and the first component in an accounting system.

Source documents are used to record transactions because they are original and show an objective report of the economic activities of each transaction. For example, when a company purchases goods from a vendor, the vendor creates a receipt or invoice that shows the goods that were purchases, the purchase price, date of transaction, seller’s name, and the method of payment. This document gives the buyer’s accounting department an objective and reliable record of the purchase transaction. It also gives the vendor a document that can used to record the sale of goods.

Source documents are also used for internal control purposes as well. For example, the manufacturing department issues a purchase requisition for the goods it needs to complete its upcoming jobs. The purchase requisition is sent to the purchasing department for approval. Once it is approved, a purchase order is issued and sent to the receiving department when the goods received are compared with the purchase order. A receiving report is issued and all three of these documents are sent to the accounting department to approve the invoice from the vendor. If all of these documents agree, the invoice is approved and the cashier issues a check for the goods.

As you can see, all of the source documents are used to ensure that only proper goods are ordered, received, and paid for.

 

Examples are:

  • Cash Memo:
    This is used for cash transactions. A Cash Memo is received or given when goods are purchased or sold for cash. Hence, all cash transactions are recorded in the books of accounts on the basis of these cash memos. The cash memo is different from Cash Receipt in the sense that it is normally issued for cash received subsequent to the sale of goods but Cash Memo is used for money received instantly.
  • Invoice or Credit Bill:An Invoice or Credit Bill is used for business transactions carried out on credit. A sales invoice is prepared to record the credit sale of goods or provision of services. The original copy of the sales invoice is sent to the purchaser and the seller keeps a duplicate copy as the proof of sale.
  • Receipts:A firm issues a receipt when it receives cash or cheques. It is an acknowledgement of receipt of cash or chequeand acts as a documentary proof for receiving the cash.
  • Deposit Slip:It is a form available from the bank for depositing money or chequein a bank account. It has a counterfoil or a carbon copy, which is returned to the depositor with signature of the cashier, as receipt. The counterfoil or a carbon copy of the deposit slip gives the details regarding the date, the amount (in cash or chequedeposited) etc.
  • Cheque:A chequeis a form made available by a Banker to its account holder. Each chequehas a counterfoil to record the same information written on the chequethat remains with the account holder for his future reference. The counterfoil is taken as a source document to make entries about payments in the books of accounts.
  • Debit Note:Debit note is a note sent to a supplier informing him that his account has been debited to the extent of goods returned to him. It is also used to send to a customer informing him that an additional amount is recoverable from him for difference in price etc.
  • Credit Note: Credit note is a note sent to a customer informing him that his account has been credited to the extent of goods returned by him or sent to a supplier informing him about the difference in price etc.
  • Bank Statement:It is a statement sent by the Bank on a regular basis, say monthly. It shows the running balance of the bank account for the period with details of deposits and payments out of the Bank Account.

Role of Source Documents in Accounting:

  • Recording basis:The source documents are the basis for recording and accounting, without which recording would be virtually meaningless.
  • Authenticates the amount paid or received:The source document establishes the amount paid or received.
  • Evidence in the court of law:The source documents can be produced in the court of law as documentary proof in the event of any dispute involving the accounting entity.
  • Basis for taxation:The tax authorities use the source documents to establish the amount of tax to be paid by the accounting entity extensively.
  • Information about make, quantity, and values:Source documents provide, in brief, the information about the model, make, quantity, amount of tax collected or payable, and the value of transactions.
  • Proof of payment or receipt:The source documents are the proof of payment made and amount received along with their purposes. For e.g., issue of account payee chequesand their record in the Bank Statement is a proof of payment.

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Annual Report

Annual Report:

An annual report is a comprehensive report on a company’s activities throughout the preceding year. Annual reports are intended to give shareholders and other interested people information about the company’s activities and financial performance.
The annual report is a financial document published by most private and public companies to summarize the major transactions of the year. The report usually begins with a letter from the Chairman of the Board and/or the Chief Executive Officer. It also includes the balance sheet, income statement and the cash flow statement as well as a discussion of company affairs and notes to the financial statements.
The joint stock companies publicly owned and listed on a stock exchange are required to prepare and publish an annual report for its shareholders. In Nepal, the privately owned companies are also required by the Companies Act, 2053 BS to prepare an annual report and submit it to the Office of the Registrar of Companies.

Components of annual report:

  1. Financial Statements:

    The financial statements consist of four statements prepared by the companies as a form of communication with its shareholders and other user groups. They include income statement, the balance sheet, statement of cash flows, and statement of changes in stockholder’s equity. The information provided in the financial statements is the responsibility of the management and subject to verification as part of the external audit.

  2. Chairperson’s Report:

    This report is an address by the Chairperson of the company’s Board of Directors to its shareholders at the Annual General Meeting (AGM). It comprises the summary of the results of financial affairs, composition of the BOD and discussion about the external environment, especially the economic and financial situation of the country and place of operation of the business. The chairperson might take this opportunity to thank and acknowledge the support and co-operation of the company’s BOD, shareholders and staff and employees.

  3. Management Discussion and Analysis:

    The management team discusses the financial statements and provides vital explanations for the amounts reported in the financial statements. Some companies report this section as financial review. The section is directed at not only simplifying the information contained in the financial statement and any back-up information requiring clarification but also providing crucial information about the company’s business plan or strategy.

  4. Management’s responsibility for financial reporting:

    It is a written statement in the annual report indicating the responsibility of management for the financial statements.

  5. Notes to Financial Statements:

    The notes to financial statements provide crucial information regarding the accounting policies and procedures adopted, the basis of taxation, the employee benefit schemes, the commitments and contingencies, the inventories, the account receivables, account payables and other details of items clubbed together to make the financial statements brief.

  6. Financial Summary:

    Another regular feature in any annual report is the summary of financial information, especially of the revenue, net income, and total assets. Many reports call it financial highlights. This section is primarily a pictorial representation using colourful pie charts, bar diagrams, or graphical curves.

  7. Report of the Independent Auditor:

    Before the annual report is presented to the company’s shareholders at the AGM and submitted to the concerned government office, the books of accounts and the financial statements of the company are subject to an external audit from an independent auditor. After such an audit, the auditor issues a report addressing to the company’s shareholders.(According to accounting standard)

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Accounting Equation

Accounting Equation,Financial Accounting I,BBA first semester,BBA-BI second semester

Accounting Equation:

The accounting equation displays that all assets are either financed by borrowing money or paying with the money of the company’s shareholders. Thus, the accounting equation is: Assets = Liabilities +Shareholder Equity. The balance sheet is a complex display of this equation, showing that the total assets of a company are equal to the total of liabilities and shareholder equity. Any purchase or sale by an accounting equity has an equal effect on both sides of the equation, or offsetting effects on the same side of the equation. The accounting equation is also written as Liabilities = Assets – Shareholder Equity and Shareholder Equity = Assets – Liabilities.

Example:

                                                    Accounting Equation for the month of march

                                                     Expert Counselling Service Incorporation

Assets = Liabilities and Owners Equity
Date Cash A/R Supplies Equipment     A/P N/P Capital Stock R/E
2-Mar 40000               40000  
7-Mar 15000             15000    
bal 55000             15000 40000  
12-Mar     700       700      
bal 55000   700       700 15000 40000  
19-Mar   4000               4000
bal 55000 4000 700       700 15000 40000 4000
20-Mar (1,300)                 (1300)
bal 53,700 4000 700       700 15000 40000 2700
22-Mar 1000 (1000)                
bal 54,700 3000 700       700 15000 40000 2700
26-Mar 2800                 2800
bal 57,500 3000 700       700 15000 40000 5500
29-Mar (8000)     8000            
bal 49,500 3000 700 8000     700 15000 40000 5500
30-Mar (3300)                 (3300)
bal 46,200 3000 700 8000     700 15000 40000 2200
31-Mar (1400)                 (1400)
  44,800 3000 700 8000     700 15000 40000  800
Total Assets=56500     Total liabilities +O/E=56500

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Worksheet

Worksheet: 

An accounting worksheet is a spreadsheet used to prepare accounting information and reports. Accounting worksheets are most often used in the accounting cycle process to draft an unadjusted trial balance, adjusting journal entries, adjusted trial balance, and financial statements.

Worksheets are prepared at the end of an accounting period and usually include a list of accounts, account balances, adjustments to each account, and each account’s adjusted balance all sorted in financial statement order. As you can imagine, after a worksheet is completely filled out, preparing financial statements manually is quite simple. Most of the preparation work goes into drafting the worksheets.

As with most working papers, accounting worksheets are designed for internal purposes only. External users like investors and creditors rarely if ever get to see a company’s accounting worksheet. This means that the worksheet format can be flexible. Companies can customize the format of their worksheets to fit their internal demands and work flow needs.

Bookkeepers and accountants use accounting worksheets for a variety of reasons. Worksheets make transferring t-accounts into an adjusted trial balance much easier. Worksheets also reduce the risk of errors making errors when producing financial statements.

Worksheets can also be used for planning purposes. Since the worksheets are used to make adjusting journal entries, managers can examine the worksheets before the adjustments are posted to see their effect on the overall financial statements. Worksheets can also be helpful in preparing interim financial statements.

Example:

 

                                     Forever Green Land Scaping

                                            August 31,2012            

 

Accounting Heads Unadjusted TB Adjustment Adjusted TB Income Statement Balance Sheet
  Debit Credit Debit Credit Debit Credit Debit Credit Debit Credit
Cash 6460       6460       6460  
Accounts Receivable 23400       23400       23400  
Supplies on hand 1260     530 730       730  
Prepaid Insurance 3675     175 3500       3500  
Equipment 28800       28800       28800  
Acc. Depn Equipmnt   9200   600   9800   Foreve   9800
Buildings 72000       72000       72000  
Acc. Depn Building   16800   200   17000       17000
Accounts Payable   10500       10500       10500
Notes Payable   10000       10000       10000
Capital Stock   40000       40000       40000
Retained Earnings   42100       42100       42100
Service Revenue   14200       14200   14200    
Advertising Expenses 1200       1200   1200      
Gasoline and Oil Expenses 1775       1775   1775      
Wages and salary Expenses 4230   3320   7550   7550      
Adjustments                    
Supplies expenses     530   530   530      
Insurance expenses     175   175   175      
Depreciation exp Equipmnt     600   600   600      
Depreciation exp Buildings     200   200   200      
Rent Receivable     700   700       700  
Rent Revenue       700   700   700    
Wages and salary payable       3320   3320       3320
Interest expenses     100   100   100      
Interest Payable       100   100       100
              2770     2770
  142800 142800 5625 5625 147720 147720 14900 14900 135590 135590

 

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Internet

  1. Internet,Advantages and Disadvantages of Internet,Services Provided by internet

    Internet:

    Internet is a global computer network providing a variety of information and communication facilities, consisting of interconnected networks using standardized communication protocols.
     

Advantages and Disadvantages of Internet:

Advantages:  1) Information on almost every subject imaginable. 2) Powerful search engines 3) Ability to do research from your home versus research libraries. 4) Information at various levels of study. Everything from scholarly articles to ones directed at children. 5) Message boards where people can discuss ideas on any topic. Ability to get wide range of opinions. People can find others that have a similar interest in whatever they are interested in. 6) The internet provides the ability of emails. Free mail service to anyone in the country. 7) Platform for products like SKYPE, which allow for holding a video conference with anyone in the world who also has access. 8) Friendships and love connections have been made over the internet by people involved in love/passion over similar interests. 9) Things such as Yahoo Answers and other sites where kids can have readily available help for homework. 10) News, of all kinds is available almost instantaneously. Commentary, on that news, from every conceivable viewpoint is also available. Disadvantages:  1) There is a lot of wrong information on the internet. Anyone can post anything, and much of it is garbage. 2) There are predators that hang out on the internet waiting to get unsuspecting people in dangerous situations. 3) Some people are getting addicted to the internet and thus causing problems with their interactions of friends and loved ones. 4) Pornography that can get in the hands of young children too easily. 5) Easy to waste a lot of time on the internet. You can start surfing, and then realize far more time has passed than you realized. Internet and television together of added to the more sedentary lifestyles of people which further exacerbates the obesity problem. 6) Internet has a lot of “cheater” sites. People can buy essays and pass them off as their own far more easily than they used to be able to do. 7) There are a lot of unscrupulous businesses that have sprung up on the internet to take advantage of people. 8) Hackers can create viruses that can get into your personal computer and ruin valuable data. 9) Hackers can use the internet for identity theft. 10) It can be quite depressing to be on the internet and realize just how uneducated so many people have become in today’s society.

A summary of advantages and disadvantages of using a internet:

Ten years ago, the Internet was practically unheard of by most people. Today, the Internet is one of the most powerful tools throughout the world. The Internet is a collection of various services and resources. The Internet’s main components are E-mail and the World Wide Web. Actually, there’s a lot more to the Internet than E-mail, search engines, celebrity web sites, up-to-the-second sports scores, and chat rooms full of discussions. The Net also ranks as one of today’s best business tools. Almost all households contain the Internet; however, before people connect to the Internet, they need to be aware of its disadvantages and advantages.

     Many people fear the Internet because of its disadvantages. They claim to not use the Internet because they are afraid of the possible consequences or are simply not interested. People who have yet connected to the Internet claim they are not missing anything. Today’s technological society must realize that it is up to them to protect themselves on the Internet.

     Children using the Internet have become a big concern. Most parents do not realize the dangers involved when their children connect to the Internet. When children are online, they can easily be lured into something dangerous. For example, children may receive pornography online by mistake; therefore, causing concern among parents everywhere. Whether surfing the Web, reading newsgroups, or using email, children can be exposed to extremely inappropriate material. To keep children safe, parents and teachers must be aware of the dangers. They must actively guide and guard their children online. There are a number of tools available today that may help keep the Internet environment safer for children.

     Musicians are also concerned with disadvantages to the Net such as, accessibility and freedom. They are upset because the Internet provides their music online at no charge to consumers. File-sharing services, such as Napster, provide copyrighted songs to all Internet users. The main concern is the music is free! Musicians feel they are not getting paid for their work. Because of Napster, it is almost impossible to close down all file-sharing services because there are too many of them to count.

     Another major disadvantage of the Internet is privacy. Electronic messages sent over the Internet can be easily tracked, revealing who is talking to whom and what they are talking about. As people surf the Internet, they are constantly giving information to web sites. People should become aware that the collection, selling, or sharing of the information they provide online increases the chances that their information will fall into the wrong hands. When giving personal information on the Internet, people should make sure the Web site is protected with a recognizable security symbol. On the other hand, this does not mean they are fully protected because anyone may obtain a user’s information. In other words, the most common Internet crimes are frauds.

     Today, not only humans getting viruses, but computers are also. Computers are mainly getting these viruses from the Internet, yet viruses may also be transferred through floppy disks. However, people should mainly be concerned about receiving viruses from the Internet. Some of these dangerous viruses destroy the computer’s entire hard drive, meaning that the user can no longer access the computer. Virus protection is highly recommended.

     Despite all of the terrible disadvantages of the Internet, there are numerous advantages. In fact, the advantages weigh out the disadvantages. The most common thing the Internet is used for is research. Children and students are among the top people who use the Internet for research. Nowadays, it is almost required that students use the Internet for research. The Internet has become one of the biggest sources for research. Almost everyday, research on medical issues becomes easier to locate. Web sites have become available for people to research diseases and talk to doctors online at sites such as, America’s Doctor.

Entertainment is another popular reason why many people surf the Internet. Downloading games, going into chat rooms or just surfing the Web are some of the uses people have discovered. There are numerous games that may be downloaded from the Internet at no charge. Chat rooms are popular because users can meet new and interesting people. In fact, the Internet has been used by people to find life long partners. When people surf the Web, there are numerous things that can be found. Music, hobbies, news and more can be found on the Internet.

     Another popular thing to do on the Internet is to check out the news. Almost all local news can be obtained through the Internet. Up to date sports scores are probably the most popular looked at news. Sports scores are updated on the Internet as soon as the game ends. Weather is also a popular source to look up on the Internet. Using the Internet to get the weather allows people to view weather all over the world. Live radar all over the country and local forecasts are just to name a few of the things that may be obtained for weather information on the Internet.

     Shopping online has also become a huge success and is considered a great advantage of the Internet. No matter what people are shopping for, it can be found on the Internet. People do not even have to leave their homes. A few companies have collected millions of dollars using the Internet for selling. Clothing is probably one of the most bought items online. Almost every major clothing store has its on Web site. In fact, In US, people can even go grocery shopping online using such sites as Priceline.com. Just one click of the mouse on the items they want to purchase and the items are delivered to their front door. Unfortunately, this kind of service is not yet available in Malaysia for the time being. Groceries and clothing are only a few of the items that may be bought on the Internet.

     In conclusion, today’s society is in the middle of a technological boom. People can either choose to take advantage of this era, or simply let it pass them by. The Internet is a very powerful tool. It has many advantages; however, people need to be extremely aware of the disadvantages as well.

Services Provided By internet:

Internet service providers (ISP – Internet Service Provider) companies or institutions (such as T-Com, Iskon or CARNet in Croatia, AT&T in US and MTNL in India), which satellite or optical connections with several major Internet node abroad (mainly in the direction of America and Europe) and the thus ensuring high capacity connection to the rest of the Internet world. However, practice has shown that it can barely follow the needs of the growing number of members of Internet communities. When selecting an ISP of significance is the number of services that it provides to its customers. All services provided by e-mail, but do not provide any service to FTP, newsgroups, renting space on the disc, certain program support and etc. CARNet allows for almost all university departments.

The Following are the most common service provided by internet.

1)Electronic Mail:

Electronic mail is one of the most popular and basic network services. It’s relatively low risk, but that doesn’t mean it’s risk free. Forging electronic mail is trivial (just as is forging regular postal mail), and forgeries facilitate two different types of attacks: attacks against your reputation and social manipulation attacks (e.g., attacks in which users are sent mail purporting to come from an administrator and advising them to change to a specific password). Accepting electronic mail ties up computer time and disk space, opening you up for denial of service attacks, although with proper configuration, only email service will be denied. Particularly with modern multimedia mail systems, people can send electronic mail containing programs that run with insufficient supervision and may turn out to be Trojan horses .

Although people worry most about the last risk mentioned above, in practice the most common problems with electronic mail are inadvertent floods (including chain letters) and people who put entirely inappropriate confidence in the confidentiality of electronic mail and send proprietary data via electronic mail across the Internet. However, as long as users are educated, and the mail service is isolated from other services so that inadvertent or purposeful denial of service attacks shut down as little as possible, electronic mail is reasonably safe.

Simple Mail Transfer Protocol ( SMTP ) is the Internet standard protocol for sending and receiving electronic mail. SMTP itself is not usually a security problem, but SMTP servers can be. A program that delivers mail to users often needs to be able to run as any user that might receive mail. This gives it broad power and makes it a tempting target for attackers.

The most common SMTP server on UNIX is Sendmail. Sendmail has been exploited in a number of break-ins, including the Internet worm, which makes people nervous about using it. Many of the available replacements, however, are not clearly preferable to Sendmail; the evidence suggests they are less exploited because they are less popular, not because they are less vulnerable. There are exceptions in programs designed explicitly for security, but these don’t support all the functions necessary to send and receive arbitrary mail messages; some things are still best handled by Sendmail running in a secured space.

2)FTP (File Transfer Protocol):

Before the World Wide Web and FTP was the only way to transfer large files between computers of Internet users. Allows access to a computer on the Internet (if it’s public or available to the password), preview content on its hard disk, finding the necessary files and copy on its own disk. This Internet service is not as simple as the World Wide Web, but it is very useful.

Using program support for FTP will set about establishing communication address is similar as in the previous examples:

 'ftp://ftp.domain.hr'              or
 'ftp://computer.domain.hr'         or
 'ftp://×××.×××.×××.×××'

File transfer function is increasingly taking the WWW, so that with a confirmation copy selected files as needed and the auxiliary program with WWW browser (GetRight or similar) which will take over the task of FTP transmission and after stop using the browser.

3)IRC (Internet Relay Chat):

This service allows the Internet to one or more of Internet users who are hooked to the same channel at the same time see the text that you type on your computer, and the texts of other active users typing on his computer. Channels to ‘talk’ to exist for almost all areas of interest. This system is much faster than e-mail because it is conducted almost simultaneously send and read messages, but it is much more expensive than e-mail, because it requires a long term connection with the Internet, but only for those who pay for this service out of his own pocket.

4)Telnet:

Internet service that allows the user logs on and runs on a remote computer and use programs installed on the remote computer. Of course, the remote computer must be enabled in the user access rights to the computer. For security reasons this service on many servers is not allowed. It is better to say that the Telnet ‘Terminal Emulation’ software support, which to communicate with a computer connected via a TCP / IP stack. Thus, the emulator work former unit called ‘Terminal’ (from the mainframe era). This same role today better performed by programs that use SSH (Secure Shell) connections over TCP / IP as the carrier of connection, but all traffic is encrypted. Although this mechanism provides plenty of security in the work with the server, system administrators are reluctant to make this service available to all users.

5)Voice / Video Communication – Skype:

Internet networking service that allows users to voice / video communication. This implies that the devices that use this service have built-in camera and microphone. Although this service is usually used for that purpose, in addition to communicate written messages, internet calls, sharing information and much more. Can be used as a common telephone communications. This service is based on the free program support allows free calls to anyone who has installed a ‘Skype’ program support on his computer, anywhere in the world. Thanks to the high speed internet communication has increasingly better quality. Can be achieved over a fixed PTT communication lines or cell phones or send text messages at very reasonable prices, without any special setup or subscriptions.

It should be emphasized that this is no communication between user devices (phones), but between two user accounts registered on ‘Skype’ service which includes registration, enter the user_name and password protected some basic personal information. The user can later modify the information in their profiles as needed. ‘Skype’ has just developed that allows retrieval of user account and select the desired action and can be installed on a PC with Windows, Mac or Linux operating system, several kinds of mobile phones, and what is best to communicate between multiple users in a commercial version it’s the conference using the ‘Skype Manager’ program support to be purchased. Provides for the use of TV sets in communication. So, a kind of free video phone, which offers even extra specific services. With this program support the new generation of smartphones and tablets, using the resources of the existing SOHO infrastructure, ‘calling’ becomes really cheap. This service should not be confused with VoIP (Voice over Internet Protocol) technology that allows the transmission of voice communications over Internet networks for the purpose of protocol design, that ‘Skype’ is used in the sense of some kind of Peer-to-Peer (P2P) communication.

Something similar is service ‘Viber‘ that allows free calls, SMS and MMS share content with anyone, anywhere, but there is no ability to transfer video as ‘Skype’. Similar to the above mentioned is service ‘WhatsApp‘, multiple platform mobile application to send messages in real time.

6)Social networks:

Social networks are a newer phenomenon and do not belong in a separate category because they contain almost all of the previously mentioned services, unified to work in an easy, friendly way. Not only does it allow communication among users but also represent a form of socializing. There are already quite developed FORUMS, bulletin boards web version, which uses a technology exchange text via the web site, or web sites. It is a debate on a topic initiated by a member of the forum. As a rule, seek enrollment, mostly for free, using the application type USER_NAME  / PASSWORD, typically associated with a user’s address in the e-mail regarding the identification. To service the forum is not abused in any way and to respect the rules of acceptable behavior take care administrators – moderators appointed by the forum owner of the forum members themselves who usually takes this obligation voluntarily reported. These individuals may be excluded from membership and delete and delete malicious content, basically supervise. Depending on the number of members, topic, traffic, and the owner of the forum depends with how the server program to use the forums.

Purpose of writing by arbitrarily selected topics has a BLOG (contraction of the term ‘web log’), a type of website that is usually maintained by an individual, is organized much like a personal diary with respect to input regarding the content of the description of an event or topic, with the possibility of enriching the content and graphics video. As a kind of diary of events, entered contests are usually displayed in reverse chronological order. Usually allows readers can add here your comments on the topic that is currently being processed..

One of the most popular is FACEBOOK, a social network where users can set up their image, disclose your personal information, describe their interests, publish their written and photographic pieces, develop some thematic discussions, etc. with the possibility that any of the members receive in ‘his ‘group or a member of it off. A sort of meeting place, so it is possible even to initiate effective political, protest, humanitarian or some other action. Has a similar purpose, and TWITTER, social networks and mikrobloging service, which uses instant messaging, SMS or web content. There are also ‘LinkedIn‘, ‘Myspace‘, ‘Tumblr‘, ‘Instagram‘ and the other, each with its own characteristics. What made them especially adorned with a tremendously rapid dissemination of information, and misinformation. Thus, the negative effects are possible.

Very specific Internet service YOUTUBE. Used to exchange video content where users can upload, view and evaluate video, up to ‘Full HD’ resolution, respecting copyrights. It is forbidden to support pornography, violence, crime, embarrassment and defamation, and advertising. For your own protection YouTube reserves the right to use, modify and delete content posted. In summary, one can find all sorts of things, from useful to useless content, but also very funny and naughty and critical to everyday events. Whether it is a film and music videos covering YouTube to be a free medium for promoting a filmmaker, musician or politician and there have been cases where people have gained popularity in this way, and then accepted by traditional media such as newspapers, radio and television.

Essentially all of these are web applications that typically require enrollment to confirm the response to the e-mail messages to prospective members. Registration is usually type USER_NAME / PASSWORD or E-MAIL / PASSWORD, and the user alone chooses who will be his personal data are visible in your profile settings. But for one such network services server is usually insufficient. Caring for their functioning in particular computers-servers; datacenter. The forerunner of the above was certainly B.B.S. era of modem communications.

7)Search Engines:

Already these social networks to enable retrieval of content that is stored and monitored, but a special group of interconnected computer servers in a DATACRNTER and interconnected datacenters in a unique system. The basic idea is that all registered facilities are located on one or more servers can be found in some sort of elaborate directory by interest groups (sports, music, movies …). For this purpose, the contents should be reported to the owner who approves the inclusion of datacenter facilities and reported its index. Advanced way of this is that all of the reported content indexes and their keywords are ranked according to their relevance. Through a simple form to enter the desired search term on the basis of which offers all of the titles that describe the content of the list according to the achieved ranking. So, basically it is a huge database that is constantly updated.

Almost every state has its own internal search engine, but the most interesting are those international type as YAHOO!, GOOGLE and BING. Are listed in the order they occurred, although they appear to their versions that preceded them, today its possibilities are not even close. Course and apply them to the desired content complying with the prescribed rules. Basically all are oriented to search HTML text or the images, though some of their skills are recognized and other formats of documents and index them. Currently qualified as a browser web content considered GOOGLE. In addition to enabling the global search and local search free within declared site. Algorithm correspondence of new titles, indexing and ranking their content daily in construction, a mechanism for storing data and their storage is not reduced more on copying disks themselves but to each other constantly copying content themselves datacenter which has quite a few in the world, about forty. Seen from the perspective described something of very great importance should be kept by them.

8)Web-Hosting (DATACENTER):

No long that it is the development of technology, high-speed computers and Internet connections, provided that the user can purchase a server in a datacenter, who cares about the correctness of the service provider, and in which the user via FTP Service set up your web content (web hosting). Of course the service is paid, but in the age of virtualization computing platforms becoming cheaper and more accessible with very reasonable prices. What set the servers and as a server lease depends on the users. This requires the lease currently available domain names and headquarters facilities in which servers become recognizable. ‘IT Alphabet’ uses just one of them and has been reported in the previously mentioned search engines. The basic difference with the search engines is that in these datacenter care about the content (data) leads users, the concern for the safety of equipment and access to available web content leading provider of these services. Impressive is the concept of ‘Google container data center‘ that uses Google.

Electronic versions of NEWSPAPERS and PERIODICALS is also one of the most important services. Main service is not fully available, in addition to the subscription, which is often not expensive and allows access to archived editions. Similar is with the offer of books and multimedia content. In addition to this specialized sites (PORTAL) offers a variety of facilities, from the amendments set out TV content, educational facilities, entertainment facilities to the ××× content. The variety is so great that it is very difficult to share content in a few categories. The above is fundamentally changing habits of users, especially the growing popularity of tablets, which are becoming, for example, an free integral part of restaurants offering. With the morning coffee not to use a paper version of the newspaper rather than a tablet. From the above it is clear why the quality of the program for viewing Internet content (browser) is given more prominence.

What has set up ‘Google’ with its ‘Android’ platform, and skillfully used ‘Facebook’ and others, and is the basis of working at recent ‘Windows’ operating systems – data storage in one location (OneDrive storage), more correctly data centers that are continuously interconnected copy and synchronize data and presented to the user as a single group – CLOUD, somewhere on the Internet, a trend that is increasingly spreading to enable the user to use their data anywhere and anytime, even with different platforms (PC, Tablet , Mobile …). To preserve the privacy of the user traffic to the cloud must be encrypted, so if security required and the data itself is encrypted. On this principle, essentially functioning banks and public institutions that offer customers a variety of services; bill payment, payment processing, issuing various documents and the like.

As usual, the service should be paid, under the principle of ‘How much money – so much music.’, But the services that are beneficial to the general welfare generally are not charged.

 

 

 

 

 

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Organizational Change

Organizational Change, Forces of Organizational change,Planned change, process of planned change

Organizational change:

Change is one of the most challenging events an organization will go through. This lesson describes the steps of the planned changed process, which include recognizing the need for change, developing change goals, appointing a change agent, assessing the current climate, developing and implementing a change plan and evaluating the plan’s success.

Organizational Change refers to relatively enduring alteration of the present state of an organization or its components or interrelation amongst the components and their differential and integrated functions in totality in order to attain greater viability in line context of the present and anticipated future environment.

Forces of Organizational Change:

External factors:

  1. Technology: –The adoption of new technologies, such as computers, telecommunication systems, robotics and flexible. Manufacturing operations have a profound impact on organizations that adopt them.
  2. Social changes: After globalization there is a radical change shift In one value placed on higher education, lifestyle, views on marriage, joint family system and shopping preferences.
  3. 3. Marketing conditions: The need, wants, appreciations, liking, disliking and preferences of customers are changing frequently. Consumer is emerging as a ‘king’ who is actually deciding factor of market forces.
  4. Globalization:-  Global economy refers that competitors likely to come from different countries. Organizations will encounter a wide variety of dynamic changes – merger, acquisition, down rising etc.
  5. Political forces:- As long as currencies fluctuate and some economies outperform other, assets will flow across borders.

                                                                                    

 

Internal forces:-

  1. 1. Changes is managerial personnel:- Changes in the functioning of top level professional manager bring changes in one organization in terms of organization design, delegation of authority, allocation of work, firing responsibility and installation of supervision and contact etc.
  2. Shift in social cultural values:  Workers are more educated, less conservative and more women are joining the work force. They place greater emphasis on human values, such as dignity recognition, social status, equality etc.
  3. To have a dynamic environment: If one organization is not moving forward, then it will not survive and grow. Flexibility, specialization, standardization, modernization and automation are the necessities of the time. Required changes should be incorporated so that employees modify their attitude towards changes.
  4. Deficiency in the existing structures: Changes may be required in the present setup of the organization to meet the challenges imposed by the workforces and technology. These deficiencies may be in the form of more no of levels, lack of cooperation and coordination, poor system of committee, lack of uniform policy decisions, multiplicity of committee autocracy in decision making, centralization and so on.

 

Planned Change:

Planned Change is constituted with intentional and goal oriented change in activities to adapt with changing environment of business. According to Thomas and Bennis, “planned change is one deliberate design and implements of a structural innovation, anew policy or goal, or a change in operating philosophy, climate, or style.” Planned change attempts at all aspects of one organization which are closely interrelated; technology, task, people, structure.

Process of Planned Change:

Change is often one of the most challenging events an organization will go through. At times it may seem like trying to climb the Himalayan  mountains barefoot! From the moment a change becomes necessary through its implementation, a great deal of factors come into play. To maximize the success of any organizational change, managers need to create and follow a logical sequence of steps to ensure the objectives of the change are accomplished. The planned change process is typically made up of the following steps:

  • Recognize the need for change
  • Develop change goals
  • Appoint a change agent
  • Assess the current climate
  • Develop a change plan method for implementation
  • Implement the plan
  • Evaluate the success of the plan at reaching the change goals

1) Recognize the Need to Change & Determine Goals: In today’s business environment there are many factors that force an organization to change. These factors can be internal to the organization (such as employees, culture, policy or procedures) or external (such as customers, competitors, the economy or politics). Managers at all levels (top, middle and low level) must be aware of these internal and external forces that potentially compromise the success of the organization and promptly respond by changing some aspect of the organization. Recognizing the need for change is pivotal to the long-term sustainability of an organization.

2) Establishing a Sense of Urgency :

Once a manager recognizes that a change should happen in the organization, he or she must be certain to understand why the change is needed. Developing change goals provides managers with the objective or expectation of how a change will respond to whatever internal or external forces are driving the need to change. For example, when Redbox made its explosive entrance into the marketplace with its movie kiosk service, Blockbuster was forced to duplicate this offering in order to stay in business. Redbox essentially created a service that literally stole the customer base from many traditional movie stores by offering the same product at a fraction of the price and at a convenient location. This required traditional movie stores like Blockbuster to recognize they needed to change what they offered as well to meet their goal of staying in business.

3) Appointing a Change Agent:

Once a manager recognizes that a change must happen in the organization and develops the change goals, he or she needs to select somebody to carry out that change. The change agent is someone who serves as a leader during change development and implementation. They are typically forward-thinking individuals who are highly charismatic, good with people and capable of inspiring the workforce to accept the change and even aid in the implementation. It is important to note that while change agents are leaders, not all leaders are change agents. In fact, many organizations will hire someone outside of the company to serve as a change agent due to their expertise and unique abilities to drive change.

4) Assess the Current Climate:

One thing that change agents are particularly good at is assessing the current climate of the organization to determine how ready the organization and its members are for the change. Some organizations are better equipped to handle change, while others take a lot more work. The change agent will spend time gathering information relating to the organizational culture, available resources, employee attitudes, possible training needs and leadership. This data is then used by the change agent to prepare people for change by offering information relating to why the change is needed, what the desired future state will be, how it is better than the current state of the organization and how the change will affect the members of the organization.

5) Developing, Implementing & Evaluating the Change:

Now that the organization has been prepared for the change, a plan is needed. Developing the change plan provides the roadmap for how the change will be implemented in such a way that the organization is able to achieve the change goals. Questions relating to who, when, where and how should all be answered in the change plan. Responsibilities are delegated, specific events and milestones are identified and the action plan is set to provide the methods and procedures that must be completed to implement the change. After the plan is written, it needs to be communicated and implemented.

Implementing the change puts the change plan into action. This is a critical time for the change agent, as he or she must maintain momentum and monitor the progress of implementation. The change agent will also pay attention to the distribution of resources, knowledge and level of employee support to ensure that barriers to successful implementation are removed. New behaviors relating to the change should also be reinforced by the change agent as a part of the implementation process.

 

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Leadership

Leadership,  Characteristics,  functions,  Traits/Qualities of Good Leaderdhip,  Styles of Leadership, Approaches to leadership(Trait Approaches to leadership,Behavioral Approaches to leadership, The Ohio State Studies, The Managerial Grid, Situational Approaches to leadership ,Fiedler Model.

Leadership:

Leadership is the ability to influence the behavior and performance of an individual or group of individuals towards the achievement of common objectives.It is a psychological process of influencing subordinates and providing guidance to them.

Characteristics of Leadership:

  1. Empathy: Creating a legitimate rapport with your staff makes it less likely that personal issues and resentment can creep in and derail the group. When your team knows that you are empathetic to their concerns, they will be more likely to work with you and share in your vision, rather than foster negative feelings.
  2. Consistency: Being a consistent leader will gain you respect and credibility, which is essential to getting buy-in from the group. By setting an example of fairness and credibility, the team will want to act the same way.
  3. Honesty: Another characteristic of leadership that lends itself to credibility. Those who are honest, especially about concerns, make it far more likely that obstacles will be addressed rather than avoided. Honesty also allows for better assessment and growth.
  4. Direction: Having the vision to break out of the norm and aim for great things -then the wherewithal to set the steps necessary to get there– is an essential characteristic of good leadership. By seeing what can be and managing the goals on how to get there, a good leader can create impressive change.
  5. Communication: Effective communication helps keep he team working on the right projects with the right attitude. If you communicate effectively about expectations, issues and advice, your staff will be more likely to react and meet your goals.
  6. Flexibility: Not every problem demands the same solution. By being flexible to new ideas and open-minded enough to consider them, you increase the likelihood that you will find the best possible answer. You will set a good example for your team and reward good ideas.
  7. Conviction: A strong vision and the willingness to see it through is one of the most important characterizes of leadership. The leader who believes in the mission and works toward it will be an inspiration and a resource to their followers.
  8. Inspiration: Quite often, employees need someone to look up to for direction, guidance, and motivation. The entrepreneur needs to be that person. Hopefully, Human Resources has hired self-motivated individuals. Nevertheless, there are times, when many employees need the boss to inspire them by word or action. Employees need someone to look up to, admire, and follow. Even when the production or delivery of services looks like “it is all going well,” the leader may at times need to step in personally to offer a suggestion or encouragement to ensure that employees perform their jobs in an optimal manner.
  9. Ambition: Resting on your laurels is bad for employee morale and entrepreneurial credibility. Employees need to be constantly striving for improvement and success; and they need to see the same and more in their leaders. When the boss is seen as someone who works to attain increasingly higher goals, employees will be impressed and more willing to mirror that behavior. It’s a win-win for everyone.
  10. Interpersonal skills: Successful entrepreneurs are comfortable relating to other people; they easily create rapport and are at least more extroverted than they are introverted. These factors help leaders seem approachable, likeable, and comfortable in their position. Those qualities contribute to staff wanting to interact with their leader. They also help motivate employees to do a better job. When workers can relate to their boss, they believe that their boss is more concerned about them, with their performance, and with their output. Furthermore, they believe that they can go to their boss with problems they encounter on the job without fearing consequences for not knowing how to resolve issues.Not all entrepreneurs are adept at interpersonal skills. Those that aren’t, might find it helpful to take a course, choose a mentor or locate a therapist to help them build interpersonal skills. The intangible cost is too high to not improve these abilities. In addition, here’s where a strong team comes into play. The less experienced leader who is still learning these skills can rely on the team to get out and to “press the flesh,” interact with employees, and spread a positive attitude to help develop morale.
  11. A “can do, get it done” attitude: Nothing builds a picture of success more than achievement, and achievement is the number one factor that motivates just about everyone across all cultures. When employees see that their boss can lead and direct, has a clear vision and attainable goals, and actually gains results in a timely manner, then that person’s credibility increases throughout the organization. Entrepreneurs must modestly demonstrate their skills to give their constituents valid reasons to appreciate and value their efforts.

Functions of Leadership:

  1.  To act as a representative of the work-group: Leader is the link between the top management and the work group. He has to communicate the problems and difficulties of the work group to the management and the expectation of the management to the work group. He act as a link between the top management and the work group.
  2.  To develop team spirit: One of the core function of the Leader manager is that to create a team spirit in between the members of the group. They should act as a team rather than performing as individuals. It is his responsibility to create a pleasant atmosphere keeping in view the subordinates needs, potential abilities and competence.
  3.  To act as a counselor of the people at work: When the subordinates face problems at work, which may be technical or emotional, the leader has to guide and advise the subordinate concerned. There may be situation which are out of control, in that situation, leader must stand behind the subordinate to encourage and support and find a solution for the problem.
  4. Proper use of Power: Leader must be careful while exercising his power or authority in relation to his subordinates. According to the situation he may exercise different types of powers like reward power, corrective power, coercive power, expert power, formal or informal power etc., for the positive response from his subordinate. Make sure that while using the power the response from his subordinate should not yield a negative response to the group work. Leader must analyze the situation before exercising his power.
  5. Time Management: Leader must ensure the timely completion of the work while ensuring the quality and efficiency of the work. At different stages, the work should be complete according to the plan. The timely completion of the individual tasks will ensure the completion of the group work. Leader should monitor and ensure the individual task at different stages are accomplished as per the plan.
  6. Secure effectiveness of group-effort: To get the maximum contribution towards the achievement of objectives the leader must delegate authority, ensure the availability of the adequate resources, provide for a reward system to improve the efficiency of capable workmen, invite participation of employees in decision making and communicate necessary information to the employees.

Styles of Leadership:

The total pattern of leaders’ actions as perceived by their employees is called leadership style. It represents the leaders’ philosophy, skills and attitudes in practice.

It is necessary to study the different leadership styles from which an appropriate style can be selected, depending upon the situation in which leadership is to be exercised and the nature of the followers involved.

1. Autocratic or Authoritarian leadership: An autocratic leader centralizes power and decision-making in himself. He gives orders, assigns tasks and duties without consulting the employees. The leader takes full authority and assumes full responsibility.Autocratic leadership is negative, based on threats and punishment. Subordinates act as he directs. He neither cares for their opinions nor permits them to influence the decision. He believes that because of his authority he alone can decide what is best in a given situation.Autocratic leadership is based upon close supervision, clear-cut direction and commanding order of the superior. It facilitates quick decisions, prompt action and unity of direction. It depends on a lesser degree of delegation. But too much use of authority might result in strikes and industrial disputes. It is likely to produce frustration and retard the growth of the capacity of employees.The employees work as hard as is necessary to avoid punishment. They will thus produce the minimum which will escape punishment.

This leadership style is less likely to be effective because (i) the new generation is more independent and less submissive and not amenable to rigid control; (ii) people look for ego satisfactions from their jobs and (iii) revolution of rising expectations changed the attitude of the people.

Autocratic leadership may be divided into three classes:

  •  The hard-boiled autocrat who relies mainly on negative influences uses the force of fear and punishment in directing his subordinates towards the organisational goals. This is likely to result in employees becoming resentful.
  • The benevolent autocrat who relies mainly on positive influences uses the reward and incentives in directing his subordinates towards the organisational goals. By using praise and pats on the back he secures the loyalty of subordinates who accept his decisions.
  • The manipulative autocrat who makes the employees feels that they are participating in decision-making though the manager himself has taken the decision. McGregor labels this style as Theory X.

2. Democratic or Participative leadership: Participative or democratic leaders decentralise authority. It is characterised by consultation with the subordinates and their participation in the formulation of plans and policies. He encourages participation in decision-making.He leads the subordinates mainly through persuasion and example rather than fear and force. Sometimes the leader serves as a moderator of the ideas and suggestions from his group. McGregor labels this style as Theory Y.Taylor’s scientific management was based on the inability of the ordinary employees to make effective decisions about their work. Hence the decision-making power was vested with the management. But recent studies indicate the need for participation by subordinates. The modern trend favours sharing the responsibility with the employees.This will foster enthusiasm in them. The employees feel that management is interested in them as well as in their ideas and suggestions. They will, therefore, place their suggestions for improvement.

Advantages for democratic leadership are as follows: (i) higher motivation and improved morale; (ii) increased co-operation with the management; (iii) improved job performance; (iv) reduction of grievances and (v) reduction of absenteeism and employee turnover.

3. The Laissez-faire or Free-rein leadership: Free-rein leaders avoid power and responsibility. The laissez-faire or non-interfering type of leader passes on the responsibility for decision-making to his subordinates and takes a minimum of initiative in administration. He gives no direction and allows the group to establish its own goals and work out its own problems.The leader plays only a minor role. His idea is that each member of the group when left to himself will put forth his best effort and the maximum results can be achieved in this way. The leader acts as an umpire. But as no direction or control is exercised over the people, the organisation is likely to flounder.

An experiment conducted among Boy Scout Clubs of the USA in 1940 shows autocratic leadership is likely to rouse antagonism in the group and produce hostility towards the leader. In democratic groups, the absence of the leader made little difference, while in autocratic groups productive work dropped to a minimum, when the leader was out of the room.

Democratic leadership is more likely to win the loyalty of the group. The laissez-faire groups also developed friendly approaches to the leader as in the democratic group. But suggestions from the groups were very low and they were also less productive.

4. Paternalistic leadership: Under this management style the leader assumes that his function is fatherly or paternal. Paternalism means papa knows best. The relationship between the leader and his group is the same as the relationship between the head of the family and the members of the family. The leader guides and protects his subordinates as members of his family.As the head of the family he provides his subordinates with good working conditions and fringe benefits. It is assumed that workers will work harder out of gratitude. This leadership style was admirably successful in Japan with her peculiar social background.

This leadership style has still been widely prevalent in small firms in India. However, this paternalistic approach is unlikely to work with mature adult employees, many of whom do not like their interests to be looked after by a “godfather.” Instead of gratitude, it might generate antagonism and resentment in the subordinates.

Approaches to Leadership:

Leadership has been one of the  most studied topics in management. Several studies on leadership have over ther year helped to develop various approaches to leadership.Broadly there are three aproaches to leadership.

1)Trait approaches to Leadership:

This style of leadership gives more credence to the qualities a person is born with rather than what they develop or the relationships they develop with followers. Leadership trait theory is the idea that people are born with certain character traits.  This is the style that is attributed to a leader who others see as “a born leader”.  The innate qualities and characteristics possessed by strong leaders.  These traits, while not totally responsible for an individual’s success as a leader, are influential in the success of the leader.  This theory assumes that if you could identify people with the correct traits, you will be able to identify leaders.

The first major approach to leadership is commonly referred to as the trait approach to leadership because the approach looks for a series of physical, mental, or personality traits that effective leaders possess that neither non-leaders nor ineffective leaders possess. We start with this approach to leadership predominantly because it’s the oldest of the major approaches to leadership and is an approach to leadership that is still very much in existence today. The first major study to synthesize the trait literature was conducted by Ralph Stogdill in 1948.Stogdill, R. M. (1948). Personal factors associated with leadership: A survey of the literature. Journal of Psychology, 25, 35-71. In 1970, Stogdill reanalyzed the literature and found six basic categories of characteristics that were associated with leadership: physical, social background, intelligence and ability, personality, task-related, and social.

The focus of each of these five traits needs to be on what people see you do–not just the things they don’t see you do. Being honest isn’t a matter of not lying–it is taking the extra effort to display honesty.Intelligence, Being smart,  Someone who knows what they are talking about will instill confidence in the followers.  But, if a leaders intelligence is too high for the followers, and there is a disconnect, this can create a problem.  A leader must communicate effectively with one’s followers, and this intelligence difference is something to keep in mind.

  1. Intelligence:Developing intelligence is a lifestyle choice.  Having strong verbal ability, perceptual ability and reasoning appears to make on a better leader.  Most people want to follow someone they feel is “smart”, able to problem solve and have strong social skills.  While it is good to be bright, a leader’s intellectual ability should not be too much from that of his or her followers. This too, would depend on the situation.
  2. Self-confidence:The ability to be certain about one’s competencies and skills. This allows the leader to move ahead because they believe that what they are doing is correct.  They have the skills to be successful.
  3. Determination:The desire to get the job done.  Individuals with determination are willing to assert themselves, take initiative and be persistent. This could also be shown as dominance.
  4. Integrity: The quality of honesty and trustworthiness.  The leader with a high level of integrity will take responsibility for his or her actions.
  5. Sociability:  This refers to a leaders ability to seek out pleasant social relationships.  Leaders with a high degree of sociability are friendly, out going, courteous, tactful and diplomatic.

2)Behavioral Approaches to leadership:

In response to the early criticisms of the trait approach, theorists began to research leadership as a set of behaviors. They evaluated what successful leaders did, developed a taxonomy of actions, and identified broad patterns that indicated different leadership styles. Behavioral theory also incorporates B.F. Skinner’s theory of behavior modification, which takes into account the effect of reward and punishment on changing behavior. An example of this theory in action is a manager or leader who motivates desired behavior by scolding employees who arrive late to meetings and showing appreciation when they are early or on time.

                                                                   The behavioral approach to leadership consists of following three studies.

a)The Ohio State Studies:

The Ohio State Leadership Studies have contributed in general to the fields of management and organizational behavior, and specifically to the field of leadership. These contributions can be summarized in several categories. Process contributions include the use of an interdisciplinary approach to the study of leadership phenomena as well as a consistent emphasis on performing high-quality research. Conceptually, the Ohio State studies helped to shift the focus of the field from a universal trait approach to a more situational, behavioral-based view. Methodologically, the Ohio State studies contributed a model of programmatic construct validation and investigation, and provided future researchers with useful research instruments. In sum, these contributions are substantial and are worthy of continued recognition. In 1945, a group of researchers at Ohio State University sought to identify the observable behaviors of leaders instead of focusing of their individual traits. To document their findings, they generated a list of 150 statements designed to measure nine different dimensions of leadership behavior. These statements were used to develop the Leaders’ Behavior Description Questionnaire (LBDQ). The surveys were then given to members of a group, who were asked to respond to a series of statements about the leader of their group. Respondents of the LBDQ-rated leaders cited how frequently they engaged in a certain behavior. The results of the survey showed that two main behaviors, consideration and initiating structure, were the most significant factors in leadership.

b)University of Michigan Studies:

Lead by the famous organizational psychologist, Dr. Rensis Likert, the leadership studies at the University of Michigan identified three characteristics of effective leadership; two of which were previously observed in studies that had been conducted at Ohio State University. The study showed that task and relationship-oriented behaviors weren’t of major significance within the world of organizational psychology. However it was the third observation that introduced a new concept, one of participative leadership. As a leading center of social science research, the University of Michigan has produced some of the most important studies of leadership. Studies dating back to the 1950s identified two broad leadership styles: an employee orientation and a production orientation. The studies also identified three critical characteristics of effective leaders: task-oriented behavior, relationship-oriented behavior, and participative leadership. The studies concluded that an employee orientation rather than a production orientation, coupled with general instead of close supervision, led to better results. The Michigan leadership studies, along with the Ohio State University studies that took place in the 1940s, are two of the best-known behavioral leadership studies and continue to be cited to this day.

c)The Managerial Grid:

Managerial Grid was originally developed by Robert Blake and Jane Mouton between 1958 and 1960 and first published in 1964 (Blake and Mouton 1964). The model was particularly influenced by Fleishman’s work on initiating structure and consideration (Blake, Mouton and Bidwell 1969; Blake and Mouton 1982b). Fleishman posited that there were two underlying dimensions of leadership behaviour which were called “consideration” and “initiating structure” (Fleishman 1957a, 1957b; Fleishman and Peters 1962). Consideration referred to behaviour reflecting respect for subordinates’ ideas and consideration of their feelings. Initiating structure referred to the extent to which a leader structured and defined his or her role and those of subordinates in order to achieve formal organisational goals. It was argued that high consideration was associated with high subordinate satisfaction, while high initiating structure was associated with high effectiveness but also high grievance levels and absenteeism. Further, it was claimed that when leaders rated high on both dimensions, high effectiveness and high satisfaction would occur without the grievance and absenteeism. Fleishman and Simmons (1970), in a representative quote, concluded “that the leadership pattern which combines high consideration and structure is likely to optimize a number of effectiveness criteria for a variety of supervisory jobs” (p. 171). This was subsequently referred to as the “high-high” leader paradigm and was the subject of research and the target for criticism during the 1970s (Larson , Hunt and Osborn 1976; Nystrom 1978).

3)Situational Approaches to Leadership:

Situational leadership is a theory of leadership that is part of a group of theories known as contingency theories of leadership. Generally speaking, contingency theories of leadership hold that a leader’s effectiveness is related to the leader’s traits or behaviors in relation to differing situational factors. According to situational leadership theory, a leader’s effectiveness is contingent on his ability to modify his management behavior to the level of his subordinates’ maturity or sophistication.

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Introduction to Management

Introduction to Management,Characteristics,Process,Principles,Manangerial levels,Manangerial skills, Managerial roles,Emerging management issues and challenges.

Definition of Management and its functions

Management is the process of reaching organizational goals by working with and through people and other organizational resources.

Management has the following 3 characteristics:

  1. It is a process or series of continuing and related activities.
  2. It involves and concentrates on reaching organizational goals.
  3. It reaches these goals by working with and through people and other organizational resources.

 

MANAGEMENT FUNCTIONS:

The 4 basic management functions that make up the management process are described in the following sections:

  1. PLANNING
  2. ORGANIZING
  3. INFLUENCING
  4. CONTROLLING.

PLANNING: Planning involves choosing tasks that must be performed to attain organizational goals, outlining how the tasks must be performed, and indicating when they should be performed.

Planning activity focuses on attaining goals. Managers outline exactly what organizations should do to be successful. Planning is concerned with the success of the organization in the short term as well as in the long term.

ORGANIZING:

Organizing can be thought of as assigning the tasks developed in the planning stages, to various individuals or groups within the organization. Organizing is to create a mechanism to put plans into action.

People within the organization are given work assignments that contribute to the company’s goals. Tasks are organized so that the output of each individual contributes to the success of departments, which, in turn, contributes to the success of divisions, which ultimately contributes to the success of the organization.

INFLUENCING:

Influencing is also referred to as motivating,leading or directing.Influencing can be defined as guiding the activities of organization members in he direction that helps the organization move towards the fulfillment of the goals.

The purpose of influencing is to increase productivity. Human-oriented work situations usually generate higher levels of production over the long term than do task oriented work situations because people find the latter type distasteful.

CONTROLLING:

Controlling is the following roles played by the manager:

  1. Gather information that measures performance
  2. Compare present performance to pre established performance norms.
  3. Determine the next action plan and modifications for meeting the desired performance parameters.

Henry Fayol’s fourteen universal principles of Mananagement

The 14 Management Principles from Henri Fayol (1841-1925) are:

1. Division of Work. Specialization allows the individual to build up experience, and to continuously improve his skills. Thereby he can be more productive.

2. Authority. The right to issue commands, along with which must go the balanced responsibility for its function.

3. Discipline. Employees must obey, but this is two-sided: employees will only obey orders if management play their part by providing good leadership.

4. Unity of Command. Each worker should have only one boss with no other conflicting lines of command.

5. Unity of Direction. People engaged in the same kind of activities must have the same objectives in a single plan. This is essential to ensure unity and coordination in the enterprise. Unity of command does not exist without unity of direction but does not necessarily flows from it.

6. Subordination of individual interest (to the general interest). Management must see that the goals of the firms are always paramount.

7. Remuneration. Payment is an important motivator although by analyzing a number of possibilities, Fayol points out that there is no such thing as a perfect system.

8. Centralization (or Decentralization). This is a matter of degree depending on the condition of the business and the quality of its personnel.

9. Scalar chain (Line of Authority). A hierarchy is necessary for unity of direction. But lateral communication is also fundamental, as long as superiors know that such communication is taking place. Scalar chain refers to the number of levels in the hierarchy from the ultimate authority to the lowest level in the organization. It should not be over-stretched and consist of too-many levels.

10. Order. Both material order and social order are necessary. The former minimizes lost time and useless handling of materials. The latter is achieved through organization and selection.

11.Equity. In running a business a „combination of kindliness and justice‟ is needed. Treating employees well is important to achieve equity.

12. Stability of Tenure of Personnel. Employees work better if job security and career progress are assured to them. An insecure tenure and a high rate of employee turnover will affect the organization adversely.

13. Initiative. Allowing all personnel to show their initiative in some way is a source of strength for the organization. Even though it may well involve a sacrifice of „personal vanity‟ on the part of many managers.

14.Esprit de Corps. Management must foster the morale of its employees. He further suggests that: “real talent is needed to coordinate effort, encourage keenness, use each person‟s abilities, and reward each one‟s merit without arousing possible jealousies and disturbing harmonious relations.”

Levels of Management,Managerial levels,Managerial Hierarchy

Managerial levels: Many managers work in an organisation. However, these managers do not work at the same level. They work and operate at different positions. Hierarchy of these managerial positions is called Levels of Management. levels of management top middle lower

1)Top Level of Management

 

The Top Level Management consists of the Board of Directors (BOD) and the Chief Executive Officer (CEO). The Chief Executive Officer is also called General Manager (GM) or Managing Director (MD) or President. The Board of Directors are the representatives of the Shareholders, i.e. they are selected by the Shareholders of the company. Similarly, the Chief Executive Officer is selected by the Board of Directors of an organisation. The main role of the top level management is summarized as follows :-

  1. The top level management determines the objectives, policies and plans of the organisation.
  2. They mobilises (assemble and bring together) available resources.
  3. The top level management does mostly the work of thinking, planning and deciding. Therefore, they are also called as the Administrators and the Brain of the organisation.
  4. They spend more time in planning and organising.
  5. They prepare long-term plans of the organisation which are generally made for 5 to 20 years.
  6. The top level management has maximum authority and responsibility. They are the top or final authority in the organisation. They are directly responsible to the Shareholders, Government and the General Public. The success or failure of the organisation largely depends on their efficiency and decision making.
  7. They require more conceptual skills and less technical Skills.

2)Middle Level of Management

 

The Middle Level Management consists of the Departmental Heads (HOD), Branch Managers, and the Junior Executives. The Departmental heads are Finance Managers, Purchase Managers, etc. The Branch Managers are the head of a branch or local unit. The Junior Executives are Assistant Finance Managers, Assistant Purchase Managers, etc. The Middle level Management is selected by the Top Level Management. The middle level management emphasize more on following tasks :-

  1. Middle level management gives recommendations (advice) to the top level management.
  2. It executes (implements) the policies and plans which are made by the top level management.
  3. It co-ordinate the activities of all the departments.
  4. They also have to communicate with the top level Management and the lower level management.
  5. They spend more time in co-ordinating and communicating.
  6. They prepare short-term plans of their departments which are generally made for 1 to 5 years.
  7. The middle Level Management has limited authority and responsibility. They are intermediary between top and lower management. They are directly responsible to the chief executive officer and board of directors.
  8. Require more managerial and technical skills and less conceptual skills.

3)Lower Level of Management

 

The lower level management consists of the Foremen and the Supervisors. They are selected by the middle level management. It is also called Operative / Supervisory level or First Line of Management. The lower level management performs following activities :-

  1. Lower level management directs the workers / employees.
  2. They develops morale in the workers.
  3. It maintains a link between workers and the middle level management.
  4. The lower level management informs the workers about the decisions which are taken by the management. They also inform the management about the performance, difficulties, feelings, demands, etc., of the workers.
  5. They spend more time in directing and controlling.
  6. The lower level managers make daily, weekly and monthly plans.
  7. They have limited authority but important responsibility of getting the work done from the workers. They regularly report and are directly responsible to the middle level management.
  8. Along with the experience and basic management skills, they also require more technical and communication skills.

 

Managerial roles

Managerial Roles:
There are many roles a manager has within an organization. Henry Mintzberg describes ten specific managerial roles most commonly seen within organizations. This lesson will discuss each of these roles and what behaviors are associated with them.

Henry Mintzberg’s Managerial Roles

There are many roles a manager has within an organization. Performing these roles is the basis of a manager’s job. To be effective at these roles, a manger must be a complete businessperson by understanding the strategic, tactical and operational responsibilities he or she holds. While not always explicitly stated in a manager’s job description, at any given moment a manager might have to be a coach, a strategic planner, a liaison, a cheerleader, a conflict manager, a realist, a problem-solver, an organizer, an optimist, a trainer and a decision-maker. These roles can change from day to day, but one thing is for sure: a manager must understand all of his or her roles and how to perform them effectively. This means that a manager must have a global understanding of all business functions, organizational goals, his or her level of accountability and the appropriate way to serve both internal and external clients of the organization.

Henry Mintzberg spent much of his career researching the managerial roles and behaviors of several chief executive officers, or CEOs. Mintzberg discovered that managers spent most of their time engaging in ten specific roles. He was able to then classify these roles into three categories, including interpersonal, informational and decisional roles. To better understand these roles, let’s look at how they are applied by Bernard the Boss as he goes through his daily routine as a manager at a local grocery store.

Interpersonal Roles:

The first category of roles described by Mintzberg is called interpersonal roles. These roles involve the behaviors associated with human interaction. In other words, interpersonal roles are those roles that allow a manager to interact with his or her employees for the purpose of achieving organizational goals. There are three roles listed under interpersonal roles, which include figurehead, leader and liaison. Let’s look at how these three roles are played out by Bernard.

When Bernard arrives at the store in the morning, he holds a daily meeting for all employees who are working that day. He spends time talking about daily specials and sales goals and motivates his employees for the day by holding a friendly contest between the workers to try to sell as many of the sale items as possible during their shift. He informs his employees that the highest seller will win a $50 gift certificate for the store. As afigurehead, Bernard the Boss has certain social, ceremonial and legal responsibilities that his employees expect him to fulfill. Bernard is seen as a source of inspiration and authority to his employees.

As Bernard goes about his day, he must make sure that he’s monitoring the performance of his employees and how well they are doing in their sales. He checks with his employees periodically to make sure they understand the products that are on sale and what key features to point out, as well as to remind them of their goal of winning the contest. Bernard the Boss’s role as aleader requires him to direct and manage the performance of his employees. He will spend time communicating performance goals, training and mentoring employees, supporting employee efforts, supplying resources, evaluating employee performance and motivating employees toward a higher level of productivity.

Bernard does not leave all the selling up to his employees, because he likes to maintain contact with his customers to better understand their needs and how he can accommodate them. He stops and chats with several customers throughout the day to get feedback on sale items and to learn about products that his customers would like to see the store put on sale in the future. Acting as a liaison is Bernard the Boss’s final interpersonal role. As a liaison, Bernard communicates with internal and external members of the organization. This networking activity is a critical step in reaching organizational goals, especially those concerned with customers.

Informational Roles:

The second category of managerial roles is informational roles. The informational roles include those roles in which a manager must generate and share knowledge to successfully achieve organizational goals. There are three roles listed under informational roles, which include monitor, disseminator and spokesperson.

After Bernard is comfortable with his employees’ understanding of the sales products and their goals, he heads back to his office to do some research for what he will put on sale next week. Bernard spends time reflecting on the feedback his employees gave and the information his customers shared with him that day, and he also looks at what his competitors are putting on sale at this time. The monitor role that Bernard the Boss must fill involves the task of researching, locating and choosing useful information. As a monitor, Bernard has to stay abreast to current industry standards and changes occurring in both the internal and external business environments. This also includes monitoring the performance of employees and their level of productivity.

Bernard combines all of the information into a proposal for next week’s sale advertisement and forwards the information to upper management for approval. He also spends some time previewing this information with his employees so that they can begin to familiarize themselves with the items. As a disseminator, Bernard must take the information he gathered as a monitor and forward it on to the appropriate individuals.

Now that Bernard has approval from upper management, he creates the advertisement for next week’s sale items and begins to distribute it to his customers. Acting as a spokesperson on behalf of the organization is Bernard’s final informational role. As a spokesperson, Bernard communicates information about the organization to outside parties.

Decisional Roles:

The third category of managerial roles according to Mintzberg is called decisional roles. Decisional roles include roles such as the entrepreneur, disturbance-handler, resource-allocator and negotiator. All of these roles involve the process of using information to make decisions.

Bernard checks in with his employees at midday and notices that some of the sale items have not done as well as anticipated. After speaking with his employees, he learns that the items that have not been selling are sitting next to the generic brand on the shelves. These generic brands are still less expensive than the sale items and are causing customers to choose the less expensive version. Bernard makes the decision to move these items to a special display area where they can sit by themselves and hopefully attract more buyers. As an entrepreneur, Bernard the Boss is focused on process improvement. He looks for ways to improve productivity and efficiency within his organization and directs the change process from development to implementation.

Managerial Skill:

Much like a professional basketball player needs to know how to dribble and shoot a basketball, or how a home builder understands the process of framing a house, managers also need to have a specific set of skills in order to effectively perform their jobs. Managerial skills are what the manager uses to assist the organization in accomplishing its goals. Specifically, a manager will make use of his or her own abilities, knowledge base, experiences, and perspectives to increase the productivity of those with whom they manage.

The toolbox for what a manager needs in order to perform their job effectively, typically, fall into one of three categories: technical skills, human skills, and conceptual skills. To give you a better understanding of these skills, let’s take a look at how each of these skills are applied by Manny the Manager and his employee Kelly the Financial Analyst.

a)Technical Skills

Technical skills are those skills needed to accomplish a specific task. It is the ‘how to’ skill set that allows a manager to complete his or her job. These skills are the combination of formal education, training, and on-the-job experience. Most employees expect their managers to have a technical skill set above their own so that, when needed, an employee can come to their manager to find out how to do something specific to their individual job.

For example, let’s say that part of Kelly the Financial Analyst’s job is to update a balance sheet each week. Kelly is a novice financial analyst and is new to the company, so she’s expecting her manager, Manny, to show her how to perform this task initially, so that she can, eventually, do it on her own. Therefore, it is essential for Manny to have the technical skills of how to update a balance sheet so that he may, in turn, share that skill with Kelly. As a low-level manager, technical skills are most important for Manny due to how close his role is to the general workforce – in this case, Kelly.

b)Human Skills:

The next type of skills a manager must have are human skills. These interpersonal skills are what a manager will use to work with his or her employees. Some people are born with good human skills; others must work much harder at it. Human skills are critical for all managers because they work with people. Managers with good human skills understand their role inside the manager/employee relationship and how important things, like trust, cohesion, fairness, empathy, and good will, are to the overall success of the organization. Human skills help the manager to communicate, lead, and motivate an employee to work towards a higher level of productivity.

For example, let’s go back to Kelly and Manny. Imagine Kelly’s job description was changing to include a greater deal of responsibility but for the same pay. Kelly is upset, and feels overwhelmed by this change. Manny is a manager with good human skills, so he is able to empathize and communicate his understanding of Kelly’s frustration with the change to her. Manny quickly works to find ways to motivate Kelly to continue to work at a higher level, despite the additional workload being placed on her.

Conceptual Skills

Conceptual skills are the final type of skills a manager must possess inside their toolbox. The level of analytical ability to envision both the parts and its sum directly translates into a manager’s conceptual skill set. Essentially, a manager’s conceptual skills allow him or her to solve problems in a strategic and calculated fashion. Conceptual skills are becoming increasingly more important in today’s chaotic business environment.

Managers are, continually, being challenged to think conceptually about their organizations to develop action plans and harness resources to achieve organizational goals. A manager with good conceptual skills can look at a problem, break it down into manageable pieces, consider a variety of possible solutions, all before putting it back together again in a more effective and efficient manner. Conceptual skills are most important for top managers but still important for middle and low-level managers as well.

 

 

Emerging management issues and challenges:

  1. Globalization: Globalization phenomenon is getting popular these days. Globalization of business refers to the free flow of goods service, technology, labor, capital information, across the national boundary; it is closer economic integration among different countries in terms of flow of good service, capital labor and technology. Globalization is the tendency of expanding business in different countries. Managers have to work in boundary less world. There is no territory or barrier in export and import business. Globalization invites global competition. Organizations which were competing locally with local competitors now they have to compete with global competitors. It is very difficult to organization to survive and develop in such situation. Organizations should increase quality of product and reduce cost which is a challenge for manager. Many organizations are becoming global these days. They are running their business in different countries with different culture, climate, and geography, political and economic system. It is a challenging work for managers to prepare executives officers who can run business in such countries.
  1. Workforce diversity: – Modern organizations are characterized by workforce diversity. Diversified workforce is the reality of business these days. Organizations are becoming heterogeneous in terms of ethnicity, gender, nationality, age group, etc. People having different religions, different nationality works together under one roof. Different people have different nature and they show different behavior because they come from different background. How to manage such diversified workforce is a great challenge for managers. If such diversified workforce is managed properly, organization will be highly benefited because they also bring diversified skill and knowledge. But, if they are not managed properly, they create serious problem.
  1. Quality assurance and productivity: – Quality is the ability of the product to satisfy customers need. How to improve quality of the product or how to assure customers about the quality of the product has become a great challenge for management. Quality ensures organizations survival and growth. Organizations use quality to compete with competitors. Only improving quality of product organizations can face the global competition. Therefore, there must be continuous improvement in quality. Quality improvement has no boundary. It is the race without final line. It is said that people buy quality not product. And, to improve quality is a really a challenge for management. Along, with increasing quality to increase productivity again is another challenge for management. Organization must try to achieve higher productivity. Higher productivity only helps to reduce cost. Productivity is the ratio between input and output. Improved technology, employees, regular skill development and better utilization of resources helps to increase productivity. Total quality management is the latest approach or needs to improve quality.
  1. Technological advancement: – How to utilize advanced and sophisticated technology has become another challenge for management. Technology has developed beyond the expectation of anybody in the world over last 100 years. Tremendous advancement has been made in production, distribution and information technology. Managers must manage all this technology with the development of computer, the face of information technology has absolutely changed. Introduction of internet, email and other electronic media, have benefitted organizations in the field of productions, distribution and other areas of business. Decision making have been facilitated by information technology. Technological advancement has changed the nature of job. Most of the jobs which were performed by unskilled and semi-skilled labors previously, now they are performed by skilled labors. Number of white collar job is increasing and blue collar jobs are decreasing. Organization must train their employees about new technology. Only with new technology, Organization can compete with other competitors.
  1. Ethics and social responsibility: – Ethics is study of how our decisions affect other people. It is the study of people’s right and duties. The moral rules the people to make decisions and the nature of relationship among people. Ethics is to follow social code of conduct, social norms, values and attitude. The decisions made by managers have a broad reach both inside and outside the organization. So, managers must follow ethical norms and consider social responsibilities. Managerial decision must be based on ethical ground. But, these days ethics id\s decreasing in business world. So, many business organizations have unethical practice. Because of the unethical practice of some business houses, all business world is blamed.

How to fulfill social responsibility is also a challenge for management. The concept of corporate social responsibility has developed. Social responsibility means obligation of business organizations towards society community, people, share holders, etc. To provide quality product at affordable price, to develop more and more employment opportunities, to carry out different development activities in society, to control pollution are some social responsibilities of business organizations.

  1. Innovation and change: – Management must pay attention on innovation and change. Otherwise, they would go out of business. Rapid innovations are taking place in technology, product and service. Product lifecycle is getting shorter and shorter. Product needs continuous improvement if the life span is to be made long. New ideas, new techniques, new methods are being innovated; there must be new inventions of ideas, new invention of product. Old and outdated product cannot satisfy customers.

There is change in external environment, political and legal, socio-cultural, economic and technological environment change rapidly. How to adjust with such change, how to keep pace with such change, how to keep pace with such change that has become challenge for management. Empowerment: – This is the age of empowerment. Role difference between management and workers has narrowed down. Status between worker and manager is very narrow. Most of the decisions are taken at operating level. Workers are free to plan and schedule their work. They are given more and more autonomy and freedom. They participate in major decision making activities. Joint goal setting and joint performance evaluation has become common. Self managed work team had been established, more and more information are given to employees, and how to manage such empower team has become challenge for managers.

 
 

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Database Management System

Database Management System,Advantages and disadvantages of DBMS,Types of DBMS,File processing system ,disadvantages,Database languages,Entity relationship diagram.

Database management system:

A database management system is the software system that allows users to define, create and maintain a database and provides controlled access to the data. A Database Management System (DBMS) is basically a collection of programs that enables users to store, modify, and extract information from a database as per the requirements. DBMS is an intermediate layer between programs and the data. Programs access the DBMS, which then accesses the data. There are different types of DBMS ranging from small systems that run on personal computers to huge systems that run on mainframes. The following are main examples of database applications: • Computerized library systems • Automated teller machines • Flight reservation systems • Computerized parts inventory systems A database management system is a piece of software that provides services for accessing a database, while maintaining all the required features of the data. Commercially available Database management systems in the market are dbase, FoxPro, IMS and Oracle, MySQL, SQL Servers and DB2 etc. These systems allow users to create update, and extract information from their databases.Compared to a manual filing system, the biggest advantages to a computerized database system are speed, accuracy, and’ accessibility.  

Advantages of DBMS:

a)Controls Redundancy: In file system, each application has its own private files, which cannot be shared between multiple applications. 1:his can often lead to considerable redundancy in the stored data, which results in wastage of storage space. By having centralized database most of this can be avoided. It is not possible that all redundancy should be eliminated. Sometimes there are sound business and technical reasons for maintaining multiple copies of the same data. In a database system, however this redundancy can be controlled.

b) Integrity can be enforced: Integrity of data means that data in database is always accurate, such that incorrect information cannot be stored in database. In order to maintain the integrity of data, some integrity constraints are enforced on the database. A DBMS should provide capabilities for defining and enforcing the constraints.

c) Inconsistency can be avoided : When the same data is duplicated and changes are made at one site, which is not propagated to the other site, it gives rise to inconsistency and the two entries regarding the same data will not agree. At such times the data is said to be inconsistent. So, if the redundancy is removed chances of having inconsistent data is also removed.

d) Data can be shared: As explained earlier, the data about Name, Class, Father __name etc. of General_Office is shared by multiple applications in centralized DBMS as compared to file system so now applications can be developed to operate against the same stored data. The applications may be developed without having to create any new stored files.

e) Standards can be enforced : Since DBMS is a central system, so standard can be enforced easily may be at Company level, Department level, National level or International level. The standardized data is very helpful during migration or interchanging of data. The file system is an independent system so standard cannot be easily enforced on multiple independent applications.

f) Restricts unauthorized access: When multiple users share a database, it is likely that some users will not be authorized to access all information in the database. For example, account office data is often considered confidential, and hence only authorized persons are allowed to access such data. In addition, some users may be permitted only to retrieve data, whereas other are allowed both to retrieve and to update. Hence, the type of access operation retrieval or update must also be controlled. Typically, users or user groups are given account numbers protected by passwords, which they can use to gain access to the database. A DBMS should provide a security and authorization subsystem, which the DBA uses to create accounts and to specify account restrictions. The DBMS should then enforce these restrictions automatically.

g)Solves Enterprise Requirement than Individual Requirement: Since many types of users with varying level of technical knowledge use a database, a DBMS should provide a variety of user interface. The overall requirements of the enterprise are more important than the individual user requirements. So, the DBA can structure the database system to provide an overall service that is “best for the enterprise”.

h) Provides Backup and Recovery: A DBMS must provide facilities for recovering from hardware or software failures. The backup and recovery subsystem of the DBMS is responsible for recovery. For example, if the computer system fails in the middle of a complex update program, the recovery subsystem is responsible for making sure that the .database is restored to the state it was in before the program started executing.

i)Cost of developing and maintaining system is lower: It is much easier to respond to unanticipated requests when data is centralized in a database than when it is stored in a conventional file system. Although the initial cost of setting up of a database can be large, but the cost of developing and maintaining application programs to be far lower than for similar service using conventional systems. The productivity of programmers can be higher in using non-procedural languages that have been developed with DBMS than using procedural languages.

j) Data Model can be developed : The centralized system is able to represent the complex data and interfile relationships, which results better data modeling properties. The data madding properties of relational model is based on Entity and their Relationship, which is discussed in detail in chapter 4 of the book.

k)Concurrency Control : DBMS systems provide mechanisms to provide concurrent access of data to multiple users.

Disadvantages of DBMS

a) Complexity : The provision of the functionality that is expected of a good DBMS makes the DBMS an extremely complex piece of software. Database designers, developers, database administrators and end-users must understand this functionality to take full advantage of it. Failure to understand the system can lead to bad design decisions, which can have serious consequences for an organization.

b) Size : The complexity and breadth of functionality makes the DBMS an extremely large piece of software, occupying many megabytes of disk space and requiring substantial amounts of memory to run efficiently.

c) Performance: Typically, a File Based system is written for a specific application, such as invoicing. As result, performance is generally very good. However, the DBMS is written to be more general, to cater for many applications rather than just one. The effect is that some applications may not run as fast as they used to.

d)Higher impact of a failure: The centralization of resources increases the vulnerability of the system. Since all users and applications rely on the ~vailabi1ity of the DBMS, the failure of any component can bring operations to a halt.

 e) Cost of DBMS: The cost of DBMS varies significantly, depending on the environment and functionality provided. There is also the recurrent annual maintenance cost.

f) Additional Hardware costs: The disk storage requirements for the DBMS and the database may necessitate the purchase of additional storage space. Furthermore, to achieve the required performance it may be necessary to purchase a larger machine, perhaps even a machine dedicated to running the DBMS. The procurement of additional hardware results in further expenditure.

g) Cost of Conversion: In some situations, the cost oftlle DBMS and extra hardware may be insignificant compared with the cost of converting existing applications to run on the new DBMS and hardware. This cost also includes the cost of training staff to use these new systems and possibly the employment of specialist staff to help with conversion and running of the system. This cost is one of the main reasons why some organizations feel tied to their current systems and cannot switch to modern database technology.

Type of Database System:

On the basis of the number of users:

• Single-user DBMS

• Multi-user DBMS  

On the basis of the site location

• Centralized DBMS

• Parallel DBMS

• Distributed DBMS

• Client/server DBMS

The database system may be multi-user or single-user. The configuration of the hardware and the size of the organization will determine whether it is a multi-user system or a single user system. In single user system the database resides on one computer and is only accessed by one user at a time. This one user may design, maintain, and write database programs. Due to large amount of data management most systems are multi-user. In this situation the data are both integrated and shared. A database is integrated when the same information is not recorded in two places. For example, both the Library department and the Account department of the college database may need student addresses. Even though both departments may access different portions of the database, the students’ addresses should only reside in one place. It is the job of the DBA to make sure that the DBMS makes the correct addresses available from one central storage area.

On the basis of site location

a)Centralized Database System:

The centralized database system consists of a single processor together with its associated data storage devices and other peripherals. It is physically confined to a single location. Data can be accessed from the multiple sites with the use of a computer network while the database is maintained at the central site. centralized database system consists of a single processor

Disadvantages of Centralized Database System

• When the central site computer or database system goes down, then every one (users) is blocked from using the system until the system comes back. • Communication costs from the terminals to the central site can be expensive.

b)Parallel Database System:

Parallel database system architecture consists of a multiple Central Processing Units (CPUs) and data storage disk in parallel. Hence, they improve processing and Input/Output (I/O) speeds. Parallel database systems are used in the application that have to query extremely large databases or that have to process an extremely large number of transactions per second.

Advantages of a Parallel Database System

• Parallel database systems are very useful for the applications that have to query extremely large databases (of the order of terabytes, for example, 1012 bytes) or that have to process an extremely large number of transactions per second (of the order of thousands of transactions per second). • In a parallel database system, the throughput (that is, the number of tasks that can be completed in a given time interval) and the response time (that is, the amount of time it takes to complete a single task from the time it is· submitted) are very high.

Disadvantages of a Parallel Database System

• In a parallel database system, there· is a startup cost associated with initiating a single process and the startup-time may overshadow the actual processing time, affecting speedup adversely. • Since process executing in a parallel system often access shared resources, a slowdown may result from interference of each new process as it completes with existing processes for commonly held resources, such as shared data storage disks, system bus and so on.

c)Distributed Database System:

A logically interrelated collection of shared data physically distributed over a computer network is called as distributed database and the software system that permits the management of the distributed database and makes the distribution transparent to users is called as Distributed DBMS.   It consists of a single logical database that is split into a number of fragments. Each fragment is stored on one or more computers under the control of a separate DBMS, with the computers connected by a communications network. As shown, in distributed database system, data is spread across a variety of different databases. These are managed by a variety of different DBMS software running on a variety of different operating systems. These machines are spread (or distributed) geographically and connected together by a variety of communication networks. logically interrelated collection of shared data physically distributed over a computer network is called as distributed database \

Advantages of Distributed Database System

• Distributed database architecture provides greater efficiency and better performance. • A single database (on server) can be shared across several distinct client (application) systems. • As data volumes and transaction rates increase, users can grow the system incrementally. • It causes less impact on ongoing operations when adding new locations. • Distributed database system provides local autonomy.  Disadvantages of Distributed Database System • Recovery from failure is more complex in distributed database systems than in centralized systems.

d)Client-Server DBMS:

Client/Server architecture of database system has two logical components namely client, and server. Clients are generally personal computers or workstations whereas server is large workstations, mini range computer system or a mainframe computer system. The applications and tools of DBMS run on one or more client platforms, while the DBMS soft wares reside on the server. The server computer is caned backend and the client’s computer is called front end. These server and client computers are connected into a network. The applications and tools act as clients of the DBMS, making requests for its services. The DBMS, in turn, processes these requests and returns the results to the client(s). Client/Server architecture handles the Graphical User Interface (GUI) and does computations and other programming of interest to the end user. The server handles parts of the job that are common to many clients, for example, database access and updates.

Multi-Tier client server computing models

In a single-tier system the database is centralized, which means the DBMS Software and the data reside in one location and the dumb terminals were used to access the DBMS as shown. single-tier system the database is centralized The rise of personal computers in businesses during the 1980s, the increased reliability of networking hardware causes Two-tier and Three-tier systems became common. In a two-tier system, different software is required for the server and for the client. Illustrates the two-tier client server model. At the early stages client server computing model was called two-tier-computing model in which client is considered as data capture and validation tier and Server was considered as data storage tier. This scenario is depicted.

Problems of two-tier architecture

 The need of enterprise scalability challenged this traditional two-tier client-server model. In the mid-1990s, as application became more complex and could be deployed to hundreds or thousands of end-users, the client side, now undergoes with following problems: two-tier client-server model • A’ fat’ client requiring considerable resources on client’s computer to run effectively. This includes disk space, RAM and CPU. • Client machines require administration which results overhead.

Three-tier architecture

By 1995, three-tier architecture appears as improvement over two-tier architecture. It has three layers, which are: • First Layer: User Interface which runs on end-user’s computer (the client) . • Second Layer: Application Server It is a business logic and data processing layer. This middle tier runs on a server which is called as Application Server. • Third Layer: Database Server It is a DBMS, which stores the data required by the middle tier. This tier may run on a separate server called the database server. As, described earlier, the client is now responsible for application’s user interface, thus it requires less computational resources now clients are called as ‘thin client’ and it requires less maintenance.

Advantages of Client/Server Database System

• Client/Server system has less expensive platforms to support applications that had previously been running only on large and expensive mini or mainframe computers • Client offer icon-based menu-driven interface, which is superior to the traditional command-line, dumb terminal interface typical of mini and mainframe computer systems. • Client/Server environment facilitates in more productive work by the users and making better use of existing data. Client/Server database system is more flexible as compared to the Centralized system • Client/Server database system is more flexible as compared to the Centralized system. • Response time and throughput is high. • The server (database) machine can be custom-built (tailored) to the DBMS function and thus can provide a better DBMS performance. • The client (application database) might be a personnel workstation, tailored to the needs of the end users and thus able to provide better interfaces, high availability, faster responses and overall improved ease of use to the user. + A single database (on server) can be shared across several distinct client (application) systems.

Disadvantages of Client/Server Database System

• Programming cost is high in client/server environments, particularly in initial phases. • There is a lack of management tools for diagnosis, performance monitoring and tuning and security control, for the DBMS, client and operating systems and networking environments.

Database Languages:

A DBMS must provide appropriate languages and interfaces for each category of users to express database queries and updates. Database Languages are used to create and maintain database on computer. There are large numbers of database languages like Oracle, MySQL, MS Access, dBase, FoxPro etc. SQL statements commonly used in Oracle and MS Access can be categorized as data definition language (DDL), data control language (DCL) and data manipulation language (DML).

 

Types

a)Data Definition Language (DDL):

It is a language that allows the users to define data and their relationship to other types of data. It is mainly used to create files, databases, data dictionary and tables within databases.It is also used to specify the structure of each table, set of associated values with each attribute, integrity constraints, security and authorization information for each table and physical storage structure of each table on disk.

b)Data Manipulation Language (DML):

It is a language that provides a set of operations to support the basic data manipulation operations on the data held in the databases. It allows users to insert, update, delete and retrieve data from the database. The part of DML that involves data retrieval is called a query language.

c)Data Control Language (DCL):

DCL statements control access to data and the database using statements such as GRANT and REVOKE. A privilege can either be granted to a User with the help of GRANT statement. The privileges assigned can be SELECT, ALTER, DELETE, EXECUTE, INSERT, INDEX etc. In addition to granting of privileges, you can also revoke (taken back) it by using REVOKE command.

File Processing System:

File processing systems was an early attempt to computerize the manual filing system that we are all familiar with. A file system is a method for storing and organizing computer files and the data they contain to make it easy to find and access them. File systems may use a storage device such as a hard disk or CD-ROM and involve maintaining the physical location of the files. In our own home, we probably have some sort of filing system, which contains receipts, guarantees, invoices, bank statements, and such like. When we need to look something up, we go to the filing system and search through the system starting from the first entry until we find what we want. Alternatively, we may have an indexing system that helps to locate what we want more quickly. For example we may have divisions in the filing system or separate folders for different types of item that are in some way logically related.The manual filing system works well when the number of items to be stored is small. It even works quite adequately when there are large numbers of items and we have only to store and retrieve them. However, the manual filing system breaks down when we have to cross-reference or process the information in the files. For example, a typical real estate agent’s office might have a separate file for each property for sale or rent, each potential buyer and renter, and each member of staff. Clearly the manual system is inadequate for this’ type of work. The file based system was developed in response to the needs of industry for more efficient data access. In early processing systems, an organization’s information was stored as groups of records in separate files.In the traditional approach, we used to store information in flat files which are maintained by the file system under the operating system’s control. Here, flat files are files containing records having no structured relationship among them. The file handling which we learn under C/C ++ is the example of file processing system. The Application programs written in C/C ++ like programming languages go through the file system to access these flat.

Characteristics of File Processing System:

• It is a group of files storing data of an organization. • Each file is independent from one another. • Each file is called a flat file. • Each file contained and processed information for one specific function, such as accounting or inventory. • Files are designed by using programs written in programming languages such as COBOL, C, C++. • The physical implementation and access procedures are written into database application; therefore, physical changes resulted in intensive rework on the part of the programmer. • As systems became more complex, file processing systems offered little flexibility, presented many limitations, and were difficult to maintain.

Limitations of the File Processing System I File-Based Approach:

1.Separated and Isolated Data: To make a decision, a user might need data from two separate files. First, the files were evaluated by analysts and programmers to determine the specific data required from each file and the relationships between the data and then applications could be written in a programming language to process and extract the needed data. Imagine the work involved if data from several files was needed.

2.Duplication of data: Often the same information is stored in more than one file. Uncontrolled duplication of data is not required for several reasons, such as: • Duplication is wasteful. It costs time and money to enter the data more than once • It takes up additional storage space, again with associated costs. • Duplication can lead to loss of data integrity; in other words the data is no longer consistent. For example, consider the duplication of data between the Payroll and Personnel departments. If a member of staff moves to new house and the change of address is communicated only to Personnel and not to Payroll, the person’s pay slip will be sent to the wrong address. A more serious problem occurs if an employee is promoted with an associated increase in salary. Again, the change is notified to Personnel but the change does not filter through to Payroll. Now, the employee is receiving the wrong salary. When this error is detected, it will take time and effort to resolve. Both these examples, illustrate inconsistencies that may result from the duplication of data. As there is no automatic way for Personnel to update the data in the Payroll files, it is difficult to foresee such inconsistencies arising. Even if Payroll is notified of the changes, it is possible that the data will be entered incorrectly.

3. Data Dependence: In file processing systems, files and records were described by specific physical formats that were coded into the application program by programmers. If the format of a certain record was changed, the code in each file containing that format must be updated. Furthermore, instructions for data storage and access were written into the application’s code. Therefore, .changes in storage structure or access methods could greatly affect the processing or results of an application. In other words, in file based approach application programs are data dependent. It means that, with the change in the physical representation (how the data is physically represented in disk) or access technique (how it is physically accessed) of data, application programs are also affected and needs modification. In other words application programs are dependent on the how the data is physically stored and accessed.

  4. Difficulty in representing data from the user’s view: To create useful applications for the user, often data from various files must be combined. In file processing it was difficult to determine relationships between isolated data in order to meet user requirements.

5. Data Inflexibility: Program-data interdependency and data isolation, limited the flexibility of file processing systems in providing users with ad-hoc information requests

6. Incompatible file formats: As the structure of files is embedded in the application programs, the structures are dependent on the application programming language. For example, the structure of a file generated by a COBOL program may be different from the structure of a file generated by a ‘C’ program. The direct incompatibility of such files makes them difficult to process jointly.

7. Data Security. The security of data is low in file based system because, the data is maintained in the flat file(s) is easily accessible. For Example: Consider the Banking System. The Customer Transaction file has details about the total available balance of all customers. A Customer wants information about his account balance. In a file system it is difficult to give the Customer access to only his data in the· file. Thus enforcing security constraints for the entire file or for certain data items are difficult.

8. Transactional Problems. The File based system approach does not satisfy transaction properties like Atomicity, Consistency, Isolation and Durability properties commonly known as ACID properties.

9. Concurrency problems. When multiple users access the same piece of data at same interval of time then it is called as concurrency of the system. When two or more users read the data simultaneously there is ll( problem, but when they like to update a file simultaneously, it may result in a problem.

10. Poor data modeling of real world. The file based system is not able to represent the complex data and interfile relationships, which results poor data modeling properties.  

 

Entity-Relationship Model:

In Entity-Relationship model a database is modeled as a collection of entities and relationship among entities. The ER model views the real world as a construct of entities and association between entities.

Entities

An entity is an object whose information is stored in the database. It is distinguishable from other objects. For example: specific person, company, event, plant. In other words, any thing that may ‘have an independent existence and about which we intend to collect data is known as Entity. It is also known as Entity type. Entities are the principal data object about which information is to be collected. Entities are usually recognizable concepts, either concrete or abstract, such as person, places, things, or events, which have relevance to the database. Some specific examples of entities are EMPLOYEES, PROJECTS, and INVOICES. An entity is analogous to a table in the relational model. Entities are classified as independent or dependent (in some methodologies, the terms used are strong and weak, respectively). An independent entity is one that does not rely on another for identification. A dependent entity is one that relies on another for identification. An entity occurrence (also called an instance) is an individual occurrence of an entity. An occurrence is analogous to a row in the relational table.

Entity Set

An entity set is a set of entities of the same type that share the same properties. For example: set of all persons, companies, trees, holidays. In object oriented terminology entity is considered as an object and entity set is considered as a class. For example, Student is an entity set or class and a particular student is an entity or an object.

Special Entity Types

Associative entities (also known as intersection entities) are entities used to associate two or more entities in order to reconcile a many-to-many relationship. Subtypes entities are used in generalization hierarchies to represent a subset of instances of their parent entity, called the super type, but which have attributes or relationships that apply only to the subset. Associative entities and generalization hierarchies are discussed in more detail in next sections.

Relationships

A Relationship represents an association between two or more entities. Relationships are classified in terms of degree, connectivity, cardinality, and existence. An example of a relationship would be: • Employees are assigned to projects • Projects have subtasks • Departments manage one or more projects

Attributes

Attributes describe the properties of the entity of which they are associated. A particular instance of an attribute is a value. For example, “Ram” is one value of the attribute Name. The domain of an attribute is the collection of all possible values an attribute can have. The domain of Name is a character string.

Attribute

We can classify attributes as following types: • Simple • Composite • Single-values • Multi-values • Derived Simple Attribute: A simple attribute is an attribute composed of a single component with an independent existence. Simple attributes cannot be further subdivided. Examples of simple attributes include Sex, Age, and Salary etc. Simple attributes are sometimes called atomic attributes.  Composite Attribute: An attribute composed of multiple components, each with an independent existence is called a composite attribute. Some attributes can be further divided to yield smaller components with an independent existence of their own. For example, the Address attribute can be composed of components like Street number, Area, City, Pin code and so on. The decision to model the Address, Area, and City etc. is dependent on whether the user view of the model refers to the Address attribute as a single unit or as individual components. Composite attributes are shown. An attribute composed of multiple components, each with an independent existence is called a composite attribute Single-valued Attribute: A single-valued attribute is one that holds a single value for a single entity. The majority of attributes are single-valued for a particular entity. For example, the Classroom entity has as single value for the room_number attribute and therefore the room_number attribute is referred to as being single-valued.   Multi-valued Attribute: A multi-valued attribute is one that holds multiple values for a single entity. Some attribute has multiple values for a particular entity. For example, a student entity can have multiple values for the Hobby attribute-reading, music, movies and so on. A multi-valued attribute may have set of numbers with upper and lower limits. For example, the Hobby attribute of a Student may have between one and five values. In other words, a student may have a minimum of one hobby and maximum of 5 hobbies. Derived Attribute: A derived attribute is one that represents a value that is derivable from the value of a related attribute or set of attributes, not necessarily in the same entity. Some attributes may be related for a particular entity. For example the Age attribute can be derived from the date-of-birth attribute and therefore they are related. We refer the age attribute as a derived attribute, the value of which is derived from the date-of-birth attribute. E-R diagram of customer entity with composite

Degreeof a Relationship

The degree of a relationship is the number of entities associated with the relationship. The n-ary relationship is the general form for degree n. Special cases are the binary, and ternary, where the degree is 2, and 3, respectively. Binary relationships, the association between two entities are the most common type in the real world. A recursive binary relationship occurs when an entity is related to itself. An example might be “some employees are married to other employees”. A ternary relationship involves three entities and is used when a binary relationship is inadequate. Many modeling approaches recognize only binary relationships. Ternary or n-ary relationships are decomposed into two or more binary relationships.

Connectivity and Cardinality

The connectivity of a relationship describes the mapping of associated entity instances in the relationship. The values of connectivity are “one” or “many”. The cardinality of a relationship is the actual number of related occurrences for each of the two entities. The basic types of connectivity for relations are: • One to One (1: 1). • One to Many (1:M) • Many to One (M:l) • Many to Many (M:M) A one-to-one (1:1) relationship is when at most one instance of an entity A is associated with one instance of entity B. For example, “employees in the company are each assigned their own office. For each employee there exists a unique office and for each office there exists a unique employee. A one-to-many (1:M) relationships is when for one instance of entity A, there are zero, one, or many instances of entity B, but for one instance of entity B, there is only one instance of entity A. Examples of l:M relationships are: • A department has many employees. • Each employee is assigned to one department. A many-to-one (M: 1) relationships is when for one instance of entity A is associated with at most one instances of entity B, but for one instance of entity B, there may be any number of instances of entity A. Examples of M: 1 relationships is • Many employees one department. A many-to-many (M: M) relationship, sometimes called non-specific, is when for one instance of entity A, there are zero, one, or many instances of entity B and for one instance of entity B there are zero, one, or many instances of entity A. Examples are: • Employees can be assigned to no more than two projects at the same time. • Projects must have assigned at least three employees. A single employee can be assigned to many projects; conversely, a single project can have assigned to it many employees. Here, the cardinality for the relationship between employees and projects is two and the cardinality between project and employee is three. Many-to-many relationships cannot be directly translated to relational tables but instead must be transformed into two or more one-to-many relationships using associative entities.

Direction

The direction of a relationship indicates the originating entity of a relationship. The entity from which a relationship originates is the parent entity; the entity where the relationship terminates is the child entity. The type of the relation is determined by the direction of line connecting relationship component and the entity. To distinguish different types of relation, we draw either a directed line or an undirected line between the relationship set and the entity set. Directed line is used to indicate one occurrence and undirected line is used to indicate many occurrences in a relation as shown in next case. To illustrate these different types of relationships consider the following entity sets: DEPARTMENT, MANAGER, EMPLOYEE, PROJECT.   The relationship between a DEPARTMENT and a MANAGER is usually one-to-one; there is only one manager per department and a manager manages only one department. This relationship between entities is shown in figure 4.3. Each entity is represent by a rectangle and a direct line indicates the relationship between them. The relationship for MANAGER to DEPARTMENT and from DEPARTMENT to MANAGER is both 1:1. Note that a one to one relationship between two entity set does not imply that for an occurrence of an entity from one set at any time there must be an occurrence of an entity in the other set. In the case of an organization, there could be times when a department is without a manager or when an employee who is classified as a manager may be without a department to manage. Some instance of one to one relationship between the entities DEP ARTMENT and MANAGER. One to One Relationship Some Instance of One to One Relationship A one to many, relationship exists from the entity MANAGER to the entity EMPLOYEE because there are several employees reporting to the manager. As we just pointed out, there could be an occurrence of the entity type MANAGER having zero occurrences of the entity type EMPLOYEE reporting to him or her. A reverse relationship, from EMPLOYEE to MANAGER, would be many to one, since a single manager may supervise many employees However, given an instance of the entity set EMPLOYEE, there could be only one instance of the entity set MANAGER to whom that employee reports (assuming that no employee reports to more than one manager). The relationship between entities is illustrated and figure shows some instances of this relationship. One to Many Relationship   Instance of One to many relationship   The relationship between the entity EMPLOYEE and the entity PROJECT can be derived as follows: Each employee could be involved in a number of different projects, and a number of employees could be working on a given project. This relationship Between EMPLOYEE and PROJECT is many to many. It is illustrated and shows some instances of such a relationship. Many to Many Relationship   Instance of M to M relationship

    Entity Relationship Diagram:

1. Gathering information: This could be a written document that describes the system in question with reasonable amount of details.

2. Producing ERD: ERD or Entity Relationship Diagram is a diagrammatic representation of the description we have gathered about the system.

3. Designing the database: Out of the ERD we have created, it is very easy to determine the tables, the attributes which the tables must contain and the relationship among these tables.

4. Normalization: This is a process of removing different kinds of impurities from the tables we have just created in the above step.

How to Prepare an ERD

 Step 1  Let us take a very simple example and we try to reach a fully organized database from it. Let us look at the following simple statement: A boy eats an ice cream. This is a description of a real word activity, and we may consider the above statement as a written document (very short, of course).

Step 2  Now we have to prepare the ERD. Before doing that we have to process the statement a little. We can see that the sentence contains a subject (boy), an object (ice cream) and a verb (eats) that defines the relationship between the subject and the object. Consider the nouns as entities (boy and ice cream) and the verb (eats) as a relationship. To plot them in the diagram, put the nouns within rectangles and the relationship within a diamond. Also, show the relationship with a directed arrow, starting from the subject entity (boy) towards the object entity (ice cream). Entity Relationship Diagram Well, fine. Up to this point the ERD shows how boy and ice cream are related. Now, every boy must have a name, address, phone number etc. and every ice cream has a manufacturer, flavor, price etc. Without these the diagram is not complete. These items which we mentioned here are known as attributes, and they must be incorporated in the ERD as connected ovals. Entity Relationship Diagram But can only entities have attributes? Certainly not. If we want then the relationship must have their attributes too. These attribute do not inform anything more either about the boy or the ice cream, but they provide additional information about the relationships between the boy and the ice cream. Entity Relationship Diagram

Step 3  We are almost complete now. If you look carefully, we now have defined structures for at least three tables like the following: Entity Relationship Diagram Entity Relationship Diagram However, this is still not a working database, because by definition, database should be “collection of related tables.” To make them connected, the tables must have some common attributes. If we chose the attribute Name of the Boy table to play the role of the common attribute, then the revised structure of the above tables become something like the following. Entity Relationship Diagram This is as complete as it can be. We now have information about the boy, about the ice cream he has eaten and about the date and time when the eating was done.  

Cardinality of Relationship  While creating relationship between two entities, we may often need to face the cardinality problem. This simply means that how many entities of the first set are related to how many entities of the second set. Cardinality can be of the following three types.

One-to-One Only one entity of the first set is related to only one entity of the second set. E.g. A teacher teaches a student. Only one teacher is teaching only one student. This can be expressed in the followingdiagram as: Entity Relationship Diagram  

One-to-Many   Only one entity of the first set is related to multiple entities of the second set. E.g. A teacher teaches students. Only one teacher is teaching many students. This can be expressed in the followingdiagram as: Entity Relationship Diagram

Many-to-One Multiple entities of the first set are related to multiple entities of the second set. E.g. Teachers teach a student. Many teachers are teaching only one student. This can be expressed in the followingdiagram as:   Entity Relationship Diagram

Many-to-Many Multiple entities of the first set is related to multiple entities of the second set. E.g. Teachers teach students. In any school or college many teachers are teaching many students. This can be consideredas a two way one-to-many relationship. This can be expressed in the following diagram as: Entity Relationship Diagram In this discussion we have not included the attributes, but you can understand that they can be used without any problem if we want to.  

The Concept of Keys  

A key is an attribute of a table which helps to identify a row. There can be many different types of keys which are explained here.  

Super Key or Candidate Key: It is such an attribute of a table that can uniquely identify a row in a table. Generally they contain unique values and can never contain NULL values. There can be more than one super key or candidate key in a table e.g. within a STUDENT table Roll and Mobile No. can both serve to uniquely identify a student.  

Primary Key: It is one of the candidate keys that are chosen to be the identifying key for the entire table. E.g. although there are two candidate keys in the STUDENT table, the college would obviously use Roll as the primary key of the table.

Alternate Key: This is the candidate key which is not chosen as the primary key of the table. They are named so because although not the primary key, they can still identify a row.

Composite Key: Sometimes one key is not enough to uniquely identify a row. E.g. in a single class Roll is enough to find a student, but in the entire school, merely searching by the Roll is not enough, because there could be 10 classes in the school and each one of them may contain a certain roll no 5. To uniquely identify the student we have to say something like “class VII, roll no 5”. So, a combination of two or more attributes is combined to create a unique combination of values, such as Class + Roll.

Foreign Key: Sometimes we may have to work with an attribute that does not have a primary key of its own. To identify its rows, we have to use the primary attribute of a related table. Such a copy of another related table’s primary key is called foreign key.  

Strong and Weak Entity  Based on the concept of foreign key, there may arise a situation when we have to relate an entity having a primary key of its own and an entity not having a primary key of its own. In such a case, the entity having its own primary key is called a strong entity and the entity not having its own primary key is called a weak entity. Whenever we need to relate a strong and a weak entity together, the ERD would change just a little.   Say, for example, we have a statement “A Student lives in a Home.” STUDENT is obviously a strong entity having a primary key Roll. But HOME may not have a unique primary key, as its only attribute Address may be shared by many homes (what if it is a housing estate?). HOME is a weak entity in this case.   The ERD of this statement would be like the following   Entity Relationship Diagram As you can see, the weak entity itself and the relationship linking a strong and weak entity must have double border.

Different Types of Database  

There are three different types of data base. The difference lies in the organization of the database and the storage structure of the data. We shall briefly mention them here.  

Relational DBMS

This is our subject of study. A DBMS is relational if the data is organized into relations, that is, tables. In RDBMS, all data are stored in the well-known row-column format.  

Hierarchical DBMS

In HDBMS, data is organized in a tree like manner. There is a parent-child relationship among data items and the data model is very suitable for representing one-to-many relationship. To access the data items, some kind of tree-traversal techniques are used, such as preorder traversal. Because HDBMS is built on the one-to-many model, we have to face a little bit of difficulty to organize a hierarchical database into row column format. For example, consider the following hierarchical database that shows four employees (E01, E02, E03, and E04) belonging to the same department D1.   Entity Relationship Diagram There are two ways to represent the above one-to-many information into a relation that is built in one-to-one relationship. The first is called Replication, where the department id is replicated a number of times in the table like the following.   Entity Relationship Diagram Replication makes the same data item redundant and is an inefficient way to store data. A better way is to use a technique called the Virtual Record. While using this, the repeating data item is not used in the table. It is kept at a separate place. The table, instead of containing the repeating information, contains a pointer to that place where the data item is stored.   Entity Relationship Diagram This organization saves a lot of space as data is not made redundant.   Network DBMS  The NDBMS is built primarily on a one–to-many relationship, but where a parent-child representation among the data items cannot be ensured. This may happen in any real world situation where any entity can be linked to any entity. The NDBMS was proposed by a group of theorists known as the Database Task Group (DBTG). What they said looks like this: In NDBMS, all entities are called Records and all relationships are called Sets. The record from where the relationship starts is called the Owner Record and where it ends is called Member Record. The relationship or set is strictly one-to-many.   In case we need to represent a many-to-many relationship, an interesting thing happens. In NDBMS, Owner and Member can only have one-to-many relationship. We have to introduce a third common record with which both the Owner and Member can have one-to-many relationship. Using this common record, the Owner and Member can be linked by a many-to-many relationship. Suppose we have to represent the statement Teachers teach students. We have to introduce a third record, suppose CLASS to which both teacher and the student can have a many-to-many relationship. Using the class in the middle, teacher and student can be linked to a virtual many-to many relationship.   Entity Relationship Diagram        

 

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