Data Information Database Database System Data 1. Known facts that can be recorded and have an implicit meaning.

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1 Database Data Information Database Database System Data 1. Known facts that can be recorded and have an implicit meaning. 2. Data is the concept of the actual information users want to store in the database 3. Anything can be a data. (raw facts & figures) 4. For example name, phone numbers and address of people you know. 5. You may have recorded this data in an indexed address book or you may stored it on a hard drive, using a personal computer and software such as Microsoft Access or Excel Database Database is collection of Data. OR An organised, persistent collection of logically related data. a very large collection of interrelated data, of an organization Databases can be as simple as the electronic address books used by individuals to keep track of recipients or as complex as electronic library systems or online flight reservation systems. Typically, some sort of query system allows users to gain access to specific information in a database. For example, electronic library systems often are designed to accept queries such as "a = author name," "t = title," and "s = subject." Therefore, the query "title = War and Peace" would retrieve all database entries which contained "War and Peace" in the title field. Let s take an example of an organization database The purchase department has to maintain records of purchase and Plan for future purchase, which depend on the current stock position maintained by stores department. Production department produces finished according to the sales order provided by the sales department Database has following properties:- A database represent some aspect of real world, sometime called miniword or universe of database. Changes in miniword are reflected in the database. (e.g., names, telephone numbers, addresses, ) 1 Anup Kumar

2 A database is designed, built, and populated with data for specific purpose. It has intended group of users and some preconceived application in which these users are interested A Database may be generated and maintained manually or it may be computerized. For example, a library card catalog is a database that may be created and maintained manually A database's tables and rows hold data in much the same way as a file cabinet or an address book, but they allow users more flexibility in what kinds of searches they can perform on the data as well as how they want to view the data Table A Table is arrange of data in a row and column format. All the data stored in the form of records(rows) and fields(columns) Record Set of information stored about a particular entity or Record is a collection of related date e.g. in file EMPLOYEE record for any employee is S.No. Employee Code, Employee Name, Date of Birth, Address, Field Name Field/column /an attribute Cardinality Degree The name of each data item is known as the field name, e.g., Employee Code, Basic, HRA etc. as shown in the Table 1. Column in a table that contains particular information about a record number of rows number of columns whose overall purpose is to record and maintain information. manipulate data via computer processing. is a software system designed to store, manage, and facilitate access to databases A Database Management System (DMS) is a combination of computer software, hardware, and information designed to electronically Database System (i) Data Hardware Software Users Database Management System (DBMS) A Database Management System (DBMS) is a software system designed to store, manage, and facilitate access to databases : A software package to facilitate the creation and maintenance of a computerized database. 2 Anup Kumar

3 Database System: The DBMS software together with the data itself. Set of programs to access the data A computer based record keeping system, It manages the database of an enterprise. - To be able to carry out operations like insertion, deletion and retrieval, the database needs to be managed by a substantial piece of software; this software is usually called a Database Management System(DBMS). - - A DBMS is usually a very large software package that enables many different tasks including the provision of facilities to enable the user to access and modify information in the database. - DBMS contains information about a particular enterprise - Manages very large amounts of data. - Supports efficient access to very large amounts of data. - Supports concurrent access to very large amounts of data. - Example: bank and its ATM machines. - Supports secure, atomic access to very large amounts of data. - Contrast two people editing the same UNIX file last to write wins with the problem if two people deduct money from the same account via ATM machines at the same time new balance is wrong whichever writes last. - DBMS provides an environment that is both convenient and efficient to use. Inserting the new data into existing data files Adding new files to the database Retrieving data from existing files Changing data in existing files Deleting data from existing files Removing existing file from the database 3 Anup Kumar

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11 Report A report is an object in Microsoft Access that is used to display and print your data in an organized manner. Reports offer a way to view, format, and summarize the information in your Microsoft Access database. For example, you can create a simple report of phone numbers for all your contacts, or a summary report on the total sales across different regions and time periods. The Navigation Pane is where you can find all of the saved reports in the database. To view your reports, make sure that all objects are visible in the Navigation Pane. What can you do with a report? A report is a database object that comes in handy when you want to present the information in your database for any of the following uses: Display or distribute a summary of data. Archive snapshots of the data. Provide details about individual records. Create labels. 11 Anup Kumar

12 Sections of a Report Report Header Page Header Page Footer Detail Section Appears at the top of the first page and displays the report title. Appears at the top of every page and displays the headings (field labels) for each column. Appears at the bottom of every page and displays the page number and total number of pages. Appears between the page header and page footer and displays the records from the table or query. Report Footer This section is optional. Appears on the last page of the report and displays summary information such as grand totals. 12 Anup Kumar

13 MS Access Query. A queryis a request for data results, and for action on data. Purpose The purpose of a query in Microsoft Access is to retrieve a particular set of data from one or more tables the query is concerned with. It can be used to group or filter the data according to the needs of the custom You can use a query to answer a simple question, to perform calculations, to combine data from different tables, or even to add, change, or delete table data. Type of Query select, append, update, delete, make table. crosstab Update Query An update query cannot be used to update data in the following types of fields: Calculated fields Fields from a totals query or a crosstab query AutoNumber fields Fields that are primary keys Fields in a union query Fields in unique-values queries and unique-records queries Cross tab Query When you want to restructure summary data to make it easier to read and understand, consider using a crosstab query. A crosstab query is a matrix, where the column headings come from the values in a field. In the example below, the product names appear down the left, the... A crosstab query calculates a sum, average, or other aggregate function, and then groups the results by two sets of values one down the side of the datasheet and the other across the top. 13 Anup Kumar

14 Creating crosstab queries When you create a crosstab query, 1. you specify which fields contain row headings, 2. which field contains column headings, and 3. which field contains values to summarize. You can use only one field each when you specify column headings and values to summarize. You can use as many as three fields when you specify row headings. Using the Crosstab Query Wizard The Crosstab Query Wizard is usually the fastest and easiest way to create a crosstab query. It does most of the work for you, but there are a few options that the wizard does not offer. The wizard has these benefits: It is easy to use. To use it, you start the wizard, and then answer a series of guided questions. It can automatically group dates into intervals. If you use a field that contains date/time data for column headings, the wizard also helps you group the dates into intervals, such as months or quarters However, by using the wizard, you cannot: Use more than one table or query as a record source. Use an expression to create fields. Add a parameter prompt. Specify a list of fixed values to use as column headings. Consider using Design view to create your crosstab query if you want to: Have more control over the process. The wizard makes some decisions for you. Use more than one table or query as a record source. Add a parameter prompt to your query. Use expressions as fields in your query. Specify a list of fixed values to use as column headings. Practice using the design grid. FORM A form in Access is a database object that you can use to create a user interface for a database application. A "bound" form is one that is directly connected to a data source such as a table or query, and can be used to enter, edit, or display data from that data source.. 14 Anup Kumar