DATABASES 1.0 INTRODUCTION 1.1 OBJECTIVES

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1 DATABASES Structure Page No. 1.0 Introduction Objectives Introduction to MS-Access Working with MS-Access Creating Database with MS-Access Interconnectivity Summary INTRODUCTION Databases are probably one of the most common use of computers to store and manage information. A database is a collection of data that is organized so that its contents can easily be accessed, managed, and updated. Databases are not specific to computers. Example of database we use in our daily life is phone book.it can store all sorts of information like Name,Phone number,address and allow quick searching. Databases allow adding, deleting, updating and retrieving of data quite easily, as well as sorting and searching. Databases were compact, fast, easy to use, current, accurate and were secure. Database is managed using a software called Database Management System(DBMS).The software allows the users to organize data into databases and helps in retrieving the data very quickly and easily. The examples of DBMS software are Microsoft Access, Oracle, Sybase etc. This unit attempts to provide you the basic skills of MS-Access database with a working knowledge of how to maintain and effectively utilize a simple database including database creation, integrity enforcement, query formulation, forms and report creation, etc. 1.1 OBJECTIVES After going through this unit, you should be able to: Create a simple Microsoft access database. Creating tables and Enter /edit records. Enforce integrity constraints on databases. Design Select queries to display data. Develop forms/reports using sample interface. Find, sort data. Connect MS-Access to different front-ends. 1

2 1.2 INTRODUCTION TO MS-ACCESS Let's start with basic terminologies used in this unit: Data: is the information needed to be stored electronically in such a way to easily use it later. Database: is a collection of related data in the subject of interest. Database Management System: is the software used to manage storing the data and inquire it. Examples of such systems are Microsoft Access, Oracle, DB2, MySQL, etc. Microsoft Access is a Relational Database Management System (RDBMS) from Microsoft. The relational data model specifies data stored in relations that have some relationships among them. It used to create small and midsize databases for the Microsoft Windows family of operating systems. It can also be used as a database server for a web-based application.in relational databases such as Sybase, Oracle, IBM DB2, MS SQL Server and MS Access, data is stored in tables made up of rows and columns. MS-Access provides you with the software tools you need to create and organize the data in a flexible manner. There are four major database components in Access namely Tables, Queries, Forms and Report. MS Access database consists of several database components. Tables : Tables are the main units of relational database where the actual data is entered. Tables consist of records (rows) and fields (columns). Queries : Queries are basically a mechanism that allow you to extract data based on the criteria you define about the data in a database. A query retrieves required fields, records, and summaries you want to see from a database. Forms : Forms provide a quick and easy way to modify and insert records into your databases.forms are nice front ends for accessing the data that is stored in database tables or that is generated by queries. Reports : A report shows selected records in a user-designed format. Pages : A data Access page is a special type of Web page designed for viewing and working with data from the Internet or an intranet. This data is stored in a Microsoft Access database or a Microsoft SQL Server database. Macros : A macro is a set of one or more actions that each performs a particular operation, such as opening a form or printing a report. Macros can help you automate common tasks. For example, you can run a macro that prints a report when a user clicks a command button. Modules :In MS Access all code is stored in "Modules".A module is a collection of Visual Basic code for Applications. 2

3 1.3 WORKING WITH MS-ACCESS Like any other computer application, in order to use Microsoft Access, you must first install it. After installing Microsoft Access, then you can open it. To start Access, click on the Start button, then the All Programs menu, then move to the MS Office menu and finally click on the Microsoft Access 2003 menu item. Your screen should look like this. The user can create a new database, or open up an existing database. In general, the first time one begins a project, Create a new file option should be used to create a blank database d. After that point, use the Open option to re-open the database created previously. By clicking Create a new file option the following screen will appear 3

4 By selecting Blank Database and clicking on the OK button, the following screen will appear in order to give the new database filename. Fill in File Name as Employee.mdb and click on the Create button to create the database. The window for the Employee database should open as shown in the figure 4

5 Microsoft Access (MS Access) enables one to manage all important information from a single database file. Within the file, one can use: Tables to store your data. Queries to find and retrieve specific data of interest. Forms to view, add, and update data in tables. Reports to analyze or print data in a specific layout. In the Objects list, click Tables the following screen will appear Click Queries the following screen will appear 5

6 Click Forms the following screen will appear Click Reports the following screen will appear 6

7 Click Pages the following screen will appear 1.4 CREATING DATABASE WITH MS-ACCESS WORKING WITH TABLES Creating a Table Using the Design View To create a table in Access using the Design View, double click on the "Create Table in Design View" item. The Table Design View will appear. Fill in the Field Name, Data Type and Description for each column/field in the table as shown in the figure 7

8 Define a primary key field before saving your table Click Save on the toolbar, and then type a name for the table. Avoid including spaces in your table name or using long names. Click View Datasheet View to begin entering data in the table. Click View Datasheet View to begin entering data in the table the following screen will appear Create a table by using wizard When Microsoft Access first starts up, a dialog box is automatically displayed with options to create a new database or open an existing one. If this dialog box is displayed, click Access Database Wizards, pages, and projects and then click OK. If you have already opened a database or closed the dialog box that displays when Microsoft Access starts up, click New Database on the toolbar. On the Databases tab, double-click the icon for the kind of database you want to create. Specify a name and location for the database. Click Create to start defining your new database 8

9 Select the sample table that we want and then select the items we need into the new table. Press next. 9

10 Enter the name of the table. 10

11 Enter the data into the table that was created through wizard. 11

12 Creating a table by entering the Data: 12

13 1.4.2 WORKING WITH QUERIES we use queries to view, change, and analyze data in different ways. You can also use them as the source of records for forms and reports. Creating a query in the design view: 13

14 If we want the details of only EmployeeID and Name then the query editor for this will be as follows: 14

15 Create a query using wizard: 15

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17 1.4.3 WORKING WITH FORMS A form is nothing more than a graphical representation of a table. You can add, update, delete records in your table by using a form. NOTE: Although a form can be named different from a table, they both still manipulate the same information and the same exact data. Hence, if you change a record in a form, it will be changed in the table also. A form is very good to use when you have numerous fields in a table. This way you can see all the fields in one screen, whereas if you were in the table view (datasheet) you would have to keep scrolling to get the field you desire. Create a form in Design view: 17

18 Create a Form using the Wizard It is a very good idea to create a form using the wizard, unless you are an advanced user and know what you are doing. Microsoft Access does a very good job of creating a form using the wizard. The following steps are needed to create a basic form: 1. Switch to the Database Window. You can do this by pressing F11 on the keyboard. 2. Click on the Forms button under Objects on the left side of screen 3. Double click on Create Form Using Wizard 4. On the next screen select the fields you want to view on your form. Most of the time you would select all of them. 5. Click Next 6. Select the layout you wish 7. Click Next 8. Select the style you desire...hint: if you plan on printing your form, I suggest you use a light background to save on printer toner and ink 9. Click Next 10. Give you form a name, and select Open the Form and enter information 11. Select Finish 12. You should see your form. To adjust the design of your form, simply hit the design button (same as with the tables), and adjust your form accordingly 18

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22 1.4.4 WORKING WITH REPORTS A report is an effective way to present your data in a printed format. Because you have control over the size and appearance of everything on a report, you can display the information the way you want to see it. Create a Report using the Wizard As with the Form, it is a very good idea to create a report using the wizard, unless you are an advanced user. Microsoft Access does a very good job using the wizard to create reports. 1. Switch to the Database Window. You can do this by pressing F11 on the keyboard. 2. Click on the Reports button under Objects on the left side of screen 3. Double click on Create Report Using Wizard 4. On the next screen select the fields you want to view on your form. Most of the time you would select all of them. 5. Click Next 6. Select if you would like to group your files. Keep repeating this step for as many groupings as you would like. 7. Click Next 8. Select the layout and the paper orientation you desire 9. Click Next 10. Select the style you desire...hint: if you plan on printing your report, I suggest you use a light background to save on printer toner and ink 11. Click Next 12. Give you report a name, and select Preview the Report 13. Select Finish 14. You should see your report. To adjust the design of your report, simply hit the design button (same as with the tables), and adjust your report accordingly. 22

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27 1.5 INTERCONNECTIVITY Using Visual Basic as a Front-End to MS-Access After launching Visual Basic and Opening a Standard Visual Basic Form, the following screen will appear 1) Create a Data Object (usually it is the second to last object on the toolbox. If you pass your mouse over, it will show Data). 2) Double click on the Data object to create an instance of the data object on your Form 27

28 3) With your property windows open (if it is not open go to view menu and select property window), select the data object (by clicking once). A window with the properties of the Data Object should appear. a. Associate a Database Name (mdb file) to the Data object. Associate the Northwind database (or any mdb file on your disk). b. Associate a RecordSource (table) to the Data object. You can associate the Customers table of the Northwind database. 28

29 4) You will now create a TextBox Field for each field that you want to access from your database table. With the property windows open, select the textbox field. Create two textboxes by double clicking on the textbox template from the tools menus. After each instance of a textbox is created on your form, drag the textbox to the appropriate position on the form. a. For the Datasource property of the field, select the name of the Data Object you defined in step 2 (it is Data1 if you haven t changed the name of the data object.. b. For the Data Field property of the textbox, select the appropriate field. Select customer If for the first textbox and contact name for the second textbox. 5) Run your program and click on the arrows to move to next record an previous record. 29

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31 Session-1 (3 hours) Question 1:Create a blank database named LIBRARY. Question 2:Add the following fields to LIBRARY: Accession Number Title Author Publisher Cost You can change the names of fields as per need. Also, assign appropriate data type and size to each field. Question 3:Add at least 10 records Question 4:Add two new fields to the above table namely, Year of publication and ISBN number. Question 5:Add data to the two new fields for all the 10 records. Question 6:Create a Form consisting of all the fields of the LIBRARY. Assign the title BOOK INFORMATION to the form. Question 7:Create a Report consisting of all the fields of the LIBRARY. Assign the title REPORT ON BOOKS. Question 8:Create a Form using Visual Basic that can accommodate all the fields of LIBRARY. Question 8:Connect the form created in Visual Basic to LIBRARY in MS-Access Question 9:View the records of LIBRARY in the form. 1.6 SUMMARY In this unit, MS-Access was introduced. Its various components as well as the process of working with it was explained. The process of creation of a database was demonstrated. Also, the process of creation of queries, forms and reports was also discussed. One of the most important features of any DBMS is its ability to connect to various front-ends. In this unit, the process of connecting Visual Basic to MS-Access is explained. 1.7 Further Readings 31

32 Access 2003 All-in-One Desk Reference for Dummies (Paperback) by John Kaufeld; 2003 Microsoft Office Access 2007 Inside Out by John Viescas and Jeffconrad;Microsoft Press; 2007 Access 2007 by Rutkosky; BPB Publications 32