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Wednesday, June 9, 2010
Databases are used to maintain and organize large amounts of related information in an efficient manner. Databases incorporate various components including tables, queries, reports, and forms. The core element however is the database table. In designing a database table, you create a set of interrelated fields of information, such as name, street address, city, and state. There are one or more key fields that uniquely identify each table entry and the other fields are related to the information in the particular key. The key and the set of values for non-key fields constitute a record. The database table is a collection of records.
Getting Started
To start, double-click on the Microsoft Office Access shortcut icon on your Desktop or alternatively click on Start > All Programs > Microsoft Office > Microsoft Office Access. On the right-hand task pane, you are given two options for staring a new database: open an existing database file or create a new file. If you want to work on an existing file you have previously saved click on the Open icon and browse the directories for your file. If you want to create a new file click on Create a new file.
Figure 1
If you have chosen to close the task pane or are using earlier versions of the software which do not display the pane, you can achieve the same by clicking on File from the menu bar and then either Open or New.
Creating a New Database File
Once you select to create a new database file, the task pane will change to allow for selecting the type of file to create. For our purposes, we will choose Blank database. A window will appear requesting a file name and a location to save the newly created database file. Give the file a name and select the folder to save it in from the Save in drop down menu at the top of the save window and click on the Create button. Once you have saved the file, you are to select what database objects you would like to create and what method to use. We will be creating four types of objects: tables, queries, forms, and reports. We will address the tables first.
Getting Started
To start, double-click on the Microsoft Office Access shortcut icon on your Desktop or alternatively click on Start > All Programs > Microsoft Office > Microsoft Office Access. On the right-hand task pane, you are given two options for staring a new database: open an existing database file or create a new file. If you want to work on an existing file you have previously saved click on the Open icon and browse the directories for your file. If you want to create a new file click on Create a new file.
Figure 1
If you have chosen to close the task pane or are using earlier versions of the software which do not display the pane, you can achieve the same by clicking on File from the menu bar and then either Open or New.
Creating a New Database File
Once you select to create a new database file, the task pane will change to allow for selecting the type of file to create. For our purposes, we will choose Blank database. A window will appear requesting a file name and a location to save the newly created database file. Give the file a name and select the folder to save it in from the Save in drop down menu at the top of the save window and click on the Create button. Once you have saved the file, you are to select what database objects you would like to create and what method to use. We will be creating four types of objects: tables, queries, forms, and reports. We will address the tables first.
Features of MS-Excell
1. Microsoft Excel is a spreadsheet program that comes with Microsoft's Office software package. Excel is a commonly used program in finance due to its ability to provide digital data organization. Excel has a variety of basic features that make it useful, even for new users who do not know how to use its more advanced functions.
Storing Data
2. Perhaps the most useful basic feature of Excel is the ability to store and organize data. Organizing data in Excel is as simple as selecting a cell in a spreadsheet and typing in the value that you want to store. A single Excel spreadsheet can contain thousands of rows and columns, allowing you to store huge amounts of data in one place. A single Excel workbook can contain many worksheets; each worksheet is a separate spreadsheet. This allows you to store many different data tables within the same Excel file.
You can create simple data tables quickly, and you can move to different cells using the "Enter" and tab keys or the arrow keys on your keyboard, rather than using the mouse pointer. You can erase data by dragging a box around the desired cells and pressing on the "Delete" key, while you can copy data to different parts of a spreadsheet simply by selecting cells and using the copy and paste functions.
Charts and Graphs
3. Another basic feature of MS Excel is the ability to create customizable charts and graphs of data. Creating a basic chart or graph is relatively simple; you must select a range of cells in the table, choose to create a graph, and specify the graph type. Excel can produce many types of graphs, such as pie charts, bar charts and line charts. Graphs are especially useful for presentations, and you can copy your graphs into MS PowerPoint slides. Formatting
4. MS Excel allows for a wide range of formatting options similar to MS Word. You can alter font size, style and color, and you can highlight cells with different colors to differentiate data values. You can also increase or decrease the size and spacing of cells to fit the data.
Formulas
5. Excel offers you the ability to enter mathematical formulas into cells to carry out calculations on other cells. Formulas can be simple or complex, and one formula may even refer to a cell that contains a value calculated using a different formula, allowing for multiple levels of calculation. Excel also has several quick calculation tools, such as column averaging and totaling.
Storing Data
2. Perhaps the most useful basic feature of Excel is the ability to store and organize data. Organizing data in Excel is as simple as selecting a cell in a spreadsheet and typing in the value that you want to store. A single Excel spreadsheet can contain thousands of rows and columns, allowing you to store huge amounts of data in one place. A single Excel workbook can contain many worksheets; each worksheet is a separate spreadsheet. This allows you to store many different data tables within the same Excel file.
You can create simple data tables quickly, and you can move to different cells using the "Enter" and tab keys or the arrow keys on your keyboard, rather than using the mouse pointer. You can erase data by dragging a box around the desired cells and pressing on the "Delete" key, while you can copy data to different parts of a spreadsheet simply by selecting cells and using the copy and paste functions.
Charts and Graphs
3. Another basic feature of MS Excel is the ability to create customizable charts and graphs of data. Creating a basic chart or graph is relatively simple; you must select a range of cells in the table, choose to create a graph, and specify the graph type. Excel can produce many types of graphs, such as pie charts, bar charts and line charts. Graphs are especially useful for presentations, and you can copy your graphs into MS PowerPoint slides. Formatting
4. MS Excel allows for a wide range of formatting options similar to MS Word. You can alter font size, style and color, and you can highlight cells with different colors to differentiate data values. You can also increase or decrease the size and spacing of cells to fit the data.
Formulas
5. Excel offers you the ability to enter mathematical formulas into cells to carry out calculations on other cells. Formulas can be simple or complex, and one formula may even refer to a cell that contains a value calculated using a different formula, allowing for multiple levels of calculation. Excel also has several quick calculation tools, such as column averaging and totaling.
Saturday, June 5, 2010
Differences between Data and Information
Differences between data and information
The interchange of the words data and information is widespread, but M150 should help you to develop a clearer understanding of the differences between the two.
Data
* Facts, statistics used for reference or analysis.
* Numbers, characters, symbols, images etc., which can be processed by a computer.
* Data must be interpreted, by a human or machine, to derive meaning
* "Data is a representation of information" *
* Latin 'datum' meaning "that which is given"
* Data plural, datum singular (M150 adopts the general use of data as singular. Not everyone agrees.)
Information
* Knowledge derived from study, experience (by the senses), or instruction.
* Communication of intelligence.
* "Information is any kind of knowledge that is exchangeable amongst people, about things, facts, concepts, etc., in some context." *
* "Information is interpreted data" *
The interchange of the words data and information is widespread, but M150 should help you to develop a clearer understanding of the differences between the two.
Data
* Facts, statistics used for reference or analysis.
* Numbers, characters, symbols, images etc., which can be processed by a computer.
* Data must be interpreted, by a human or machine, to derive meaning
* "Data is a representation of information" *
* Latin 'datum' meaning "that which is given"
* Data plural, datum singular (M150 adopts the general use of data as singular. Not everyone agrees.)
Information
* Knowledge derived from study, experience (by the senses), or instruction.
* Communication of intelligence.
* "Information is any kind of knowledge that is exchangeable amongst people, about things, facts, concepts, etc., in some context." *
* "Information is interpreted data" *
DBMS
A Database Management System (DBMS) is a set of computer programs that controls the creation, maintenance, and the use of the database with computer as a platform or of an organization and its end users. It allows organizations to place control of organization-wide database development in the hands of database administrators (DBAs) and other specialists. A DBMS is a system software package that helps the use of integrated collection of data records and files known as databases. It allows different user application programs to easily access the same database. DBMSs may use any of a variety of database models, such as the network model or relational model. In large systems, a DBMS allows users and other software to store and retrieve data in a structured way. Instead of having to write computer programs to extract information, user can ask simple questions in a query language. Thus, many DBMS packages provide Fourth-generation programming language (4GLs) and other application development features. It helps to specify the logical organization for a database and access and use the information within a database. It provides facilities for controlling data access, enforcing data integrity, managing concurrency controlled, restoring database.
Friday, June 4, 2010
Using the SUM Feature of MS EXCEL
Using the SUM Function
The SUM function in Excel is specifically designed to add values from different ranges. The SUM Function can be typed into a cell in Excel, or inserted via the Insert Function tool to the left of your Formula bar. The syntax of the SUM Function is SUM(number1,number2, ...). SUM is the function name, and contained within the brackets are "arguments", or the pieces of information that Excel requires to complete the Function. The SUM function allows from 1 to 30 arguments (number 1, number ....) for which you require the total value or SUM.
Using Ctrl to Mark Cells
If you wish to add cells that are non-contiguous (not joined together), type in your function =SUM( click in the first cell you wish to add. Hold down your Ctrl key and click in all other cells you wish to add up, then type in a ). Typing in a comma instead of selecting with your Ctrl key also works just as efficiently as well.
Using SUM to Add a Range from a Different Worksheet.
You can easily use SUM to add up the same range in different worksheets. Click in the cell you want the result of your addition in, then holding down the Shift key, click on the next worksheet that you wish to include in your calculation and highlight the range to be used, then click Enter.
One thing to note here however, is that if you insert a worksheet in the middle of the range that you have told the SUM function to add, then the same range on that worksheet will be included in your sum.
TIP! If you wish to force any new inserted worksheets to be included in the SUM range, try this. insert a blank worksheet at the beginning of your sheets in your workbook, and a blank sheet at the end. Now in the cell that you wish the result of your addition to appear in type in =SUM( and then click on the new first blank worksheet and highlight the range you require to be added in all worksheets.
Hold down your Shift key and click on the new last blank worksheet, then close your bracket ) and hit enter. Now hide the first sheet and the last sheet by going to Format>Sheet>Hide. This will force any new worksheets to be included in the SUM range as all new worksheets will be between the 2 blank ones.
The SUM function in Excel is specifically designed to add values from different ranges. The SUM Function can be typed into a cell in Excel, or inserted via the Insert Function tool to the left of your Formula bar. The syntax of the SUM Function is SUM(number1,number2, ...). SUM is the function name, and contained within the brackets are "arguments", or the pieces of information that Excel requires to complete the Function. The SUM function allows from 1 to 30 arguments (number 1, number ....) for which you require the total value or SUM.
Using Ctrl to Mark Cells
If you wish to add cells that are non-contiguous (not joined together), type in your function =SUM( click in the first cell you wish to add. Hold down your Ctrl key and click in all other cells you wish to add up, then type in a ). Typing in a comma instead of selecting with your Ctrl key also works just as efficiently as well.
Using SUM to Add a Range from a Different Worksheet.
You can easily use SUM to add up the same range in different worksheets. Click in the cell you want the result of your addition in, then holding down the Shift key, click on the next worksheet that you wish to include in your calculation and highlight the range to be used, then click Enter.
One thing to note here however, is that if you insert a worksheet in the middle of the range that you have told the SUM function to add, then the same range on that worksheet will be included in your sum.
TIP! If you wish to force any new inserted worksheets to be included in the SUM range, try this. insert a blank worksheet at the beginning of your sheets in your workbook, and a blank sheet at the end. Now in the cell that you wish the result of your addition to appear in type in =SUM( and then click on the new first blank worksheet and highlight the range you require to be added in all worksheets.
Hold down your Shift key and click on the new last blank worksheet, then close your bracket ) and hit enter. Now hide the first sheet and the last sheet by going to Format>Sheet>Hide. This will force any new worksheets to be included in the SUM range as all new worksheets will be between the 2 blank ones.
Thursday, June 3, 2010
Computer, Types , Functions
• Computer:
A computer is an electronic device that processs data, converting it into information that is useful to people. Any computer is controlle by programmed instructions, which give the machine a purpose and guide it what to do.
•
• •
•
• The first step of solving a problem a a computsfs is to develop a computer program and them store it in the memory. The computer them executes the instructions in the program. The instructions generally direct the computer to perform three basic functions over and over again; these are processing, output. Collectively, these functions constitute the data processing cycle.
• Input: Input devices feed the computer facts or data to be processed.
• Processing: The control and storing of data, numerical comparisons and arithmetic operations are performed on the input data to produce the results.
• Output: The computer feeds the processed data or information to the output devices.
A computer reads a program and stores it in the memory and executes instructions to:
• Input data from disk, keyboard, and other storage media.
• Process data and
• Output results to display screen, disk or other media.
A computer is an electronic device that processs data, converting it into information that is useful to people. Any computer is controlle by programmed instructions, which give the machine a purpose and guide it what to do.
•
• •
•
• The first step of solving a problem a a computsfs is to develop a computer program and them store it in the memory. The computer them executes the instructions in the program. The instructions generally direct the computer to perform three basic functions over and over again; these are processing, output. Collectively, these functions constitute the data processing cycle.
• Input: Input devices feed the computer facts or data to be processed.
• Processing: The control and storing of data, numerical comparisons and arithmetic operations are performed on the input data to produce the results.
• Output: The computer feeds the processed data or information to the output devices.
A computer reads a program and stores it in the memory and executes instructions to:
• Input data from disk, keyboard, and other storage media.
• Process data and
• Output results to display screen, disk or other media.
Mini Computer v Micro Computer
Mini Computer which is great/large than micro computer but smaller than mainframe computer is called Mini Computer. Certainly it can be set up on a medium scale table; its weight is not more than 25 kg, Terminal facilities are avialable here.
Mini computer is also used is statistical and Banking purposes.
Example-IBM S/34, IBM S/36, IBM AS/400 etc.
Mini computer is also used is statistical and Banking purposes.
Example-IBM S/34, IBM S/36, IBM AS/400 etc.
Computer Generations
Development over the years have resulted in machines with greatly increased speeds, storage, memory, and computing power. The developments were so far-reaching and numerous that they are generally categorized by generations. Each generation is initiated by significant advances in computer hardware or computer software.
• First Generation (1942-1959): First-generation computers utilized vacuum tubes in their circuitry and for storage of data and instructions. The vacuum tube was bully, caused tremendous heat problems, and was never a reliable device, it caused a great number of breakdowns and inefficient operations. [Magnetic cords began to replace vacuum tubes as the principal memory device in the early machine. Small doughnut-shaped cores were strung on wires within the computer.] Programs were written in machine language employing combinations of 0 and 1. Examples of first generation computers are IBM 650, IBM 7O4, IBM 705, IBM 709, Mark II, Mark III etc.
• Second Generation (1960-1965) The second generation computers raw the replacement of the vacuum tubes by transistor can be thought of as a switch, but no moving parts. Because of high speed operation and small size, computers of this generation could perform a single operation in microseconds and were capable of storing tens of thousands of characters. [Manufactures began producing business-oriented computers with more efficient storage and faster input and output capabilities. Second generation computers efficient storage and faster input and output capabilities. Second generation computers were reliable, compact in size, virtually free of heat problems.] Programming was done in both machine and symbolic languages. Symbolic languages utilize symbolic names for computer commands and allow the use of symbolic names for items of data. This language is also known as assembly language. Examples of second generation computers are: IBM 1400, CDC 1604, RCA 501, NCR 300, GE 200, IBM 1600 etc.
• Third Generation (1965-1971) These computers were characterized by integrated circuits with component so small that in many cases they were hardly visible to the naked eye. Third generation computers wre characterized by increased input/output, storage, and processing capabilities. Input/output devices could communicate with computers over distances via ordinary telephone lines or could scan a said and input the information directly into the computer even accept voice input.
Storage capabilities wre increased and millions of characters could be stored and randomly accesssed in fractions of a second. Third-generation computers could process instructions in nanoseconds. In addition, computers were able to process several programs or sets of instructions simultaneously. Programmmers were able to make use of high-level problem oriented and procedure oriented languages that closely resembles the commonly used form of expressions. Examples of third generation computers are IBM 360, IBM 370, PDP-8, PDP-11, GE 600 etc.
• Fourth Generation (1972-Present) The fourth generation computers posses still greater input/output, storage, and processing capabilities. In the fourth generation computers, semiconductor storage devices were introduced. In the early 1970s IBM introduced the concept of virtual storage into their 5000 and 370 series of computers. Machines previously limited to a maximum internal storage capability in billions and trillions of characters. With this capability a machine could execute a program many times the size of the machine's actual memory. Microcomputers using microprocessors as the CPU proliferated in the fourth generation.
Now a days, the compact disk (CD) promises to become the data storage medium of choice. A compact disk read-only memory (CD-ROM) is encoded with on and off bits. Bits are stored on the disk's (3.5-inch diameter) aluminum surface as tiny pits at varying depths. The average CD can store about 4,800 million bits or 600 million characters of data. This is approximately a quarter of a million pages of text.
The most impressive advancement has occured in software. As a result of these changes, access to substantial computer power, previously only affordable by very large business concerns, is now economically feasible for small business and personal applications. Personal computers are examples of fourth generation microcomputers.
• Fifth Generation
Fifth generation of computers is yet to come. They will be capable of reasoning, learning, making inferences and behaving in ways usually considered exclusive of humans. These computers will be drugsed with massive primary-storage capabilities and extremely fast processing speeds. Software will proliferate and get much bigger. Hardware will continue to shrink in size but internal memory will increase dramatically. "Talking machines" will be common place. Voice-recognition, the ability for a machine to understand and obey spoken words will be developed. Industrial and personal robots will roll and wall. Experts systems software will place the knowledge of experts and consultants (such as doctors, lawyers and teachers) as the disposal of general power of an inconceivable magnitude. Artificial intelligence will be used extensively to enhance the system behavior in the future.
• First Generation (1942-1959): First-generation computers utilized vacuum tubes in their circuitry and for storage of data and instructions. The vacuum tube was bully, caused tremendous heat problems, and was never a reliable device, it caused a great number of breakdowns and inefficient operations. [Magnetic cords began to replace vacuum tubes as the principal memory device in the early machine. Small doughnut-shaped cores were strung on wires within the computer.] Programs were written in machine language employing combinations of 0 and 1. Examples of first generation computers are IBM 650, IBM 7O4, IBM 705, IBM 709, Mark II, Mark III etc.
• Second Generation (1960-1965) The second generation computers raw the replacement of the vacuum tubes by transistor can be thought of as a switch, but no moving parts. Because of high speed operation and small size, computers of this generation could perform a single operation in microseconds and were capable of storing tens of thousands of characters. [Manufactures began producing business-oriented computers with more efficient storage and faster input and output capabilities. Second generation computers efficient storage and faster input and output capabilities. Second generation computers were reliable, compact in size, virtually free of heat problems.] Programming was done in both machine and symbolic languages. Symbolic languages utilize symbolic names for computer commands and allow the use of symbolic names for items of data. This language is also known as assembly language. Examples of second generation computers are: IBM 1400, CDC 1604, RCA 501, NCR 300, GE 200, IBM 1600 etc.
• Third Generation (1965-1971) These computers were characterized by integrated circuits with component so small that in many cases they were hardly visible to the naked eye. Third generation computers wre characterized by increased input/output, storage, and processing capabilities. Input/output devices could communicate with computers over distances via ordinary telephone lines or could scan a said and input the information directly into the computer even accept voice input.
Storage capabilities wre increased and millions of characters could be stored and randomly accesssed in fractions of a second. Third-generation computers could process instructions in nanoseconds. In addition, computers were able to process several programs or sets of instructions simultaneously. Programmmers were able to make use of high-level problem oriented and procedure oriented languages that closely resembles the commonly used form of expressions. Examples of third generation computers are IBM 360, IBM 370, PDP-8, PDP-11, GE 600 etc.
• Fourth Generation (1972-Present) The fourth generation computers posses still greater input/output, storage, and processing capabilities. In the fourth generation computers, semiconductor storage devices were introduced. In the early 1970s IBM introduced the concept of virtual storage into their 5000 and 370 series of computers. Machines previously limited to a maximum internal storage capability in billions and trillions of characters. With this capability a machine could execute a program many times the size of the machine's actual memory. Microcomputers using microprocessors as the CPU proliferated in the fourth generation.
Now a days, the compact disk (CD) promises to become the data storage medium of choice. A compact disk read-only memory (CD-ROM) is encoded with on and off bits. Bits are stored on the disk's (3.5-inch diameter) aluminum surface as tiny pits at varying depths. The average CD can store about 4,800 million bits or 600 million characters of data. This is approximately a quarter of a million pages of text.
The most impressive advancement has occured in software. As a result of these changes, access to substantial computer power, previously only affordable by very large business concerns, is now economically feasible for small business and personal applications. Personal computers are examples of fourth generation microcomputers.
• Fifth Generation
Fifth generation of computers is yet to come. They will be capable of reasoning, learning, making inferences and behaving in ways usually considered exclusive of humans. These computers will be drugsed with massive primary-storage capabilities and extremely fast processing speeds. Software will proliferate and get much bigger. Hardware will continue to shrink in size but internal memory will increase dramatically. "Talking machines" will be common place. Voice-recognition, the ability for a machine to understand and obey spoken words will be developed. Industrial and personal robots will roll and wall. Experts systems software will place the knowledge of experts and consultants (such as doctors, lawyers and teachers) as the disposal of general power of an inconceivable magnitude. Artificial intelligence will be used extensively to enhance the system behavior in the future.
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