Database

A database is an application utilized to systematically store information. It comprises a structured collection of data or records.

A database management system (DBMS) is a compilation of computer software that empowers users to establish, generate, and uphold a database. Functioning as a computer application, a DBMS interacts with users, other applications, and the database itself to capture and analyze data.

The primary objective of a database management system (DBMS) is to facilitate the creation, definition, querying, and administration of a database. It serves as an intermediary between the database and end users or application programs, ensuring consistent organization and easy accessibility of data. Database Administrators oversee the database system, including access and security aspects.

DBMS Functions

A DBMS enables users to generate, modify, and update data in database files. Its functions encompass:

1. Simultaneous access to the same database concurrently.
2. Establishment of security protocols for user access rights.
3. Enhancement of data integrity within the database.
4. Provision of a data dictionary for data descriptions.

Examples of Database Management Packages:

Diverse types of database management systems are available, including:

1. Microsoft Access: Developed by Microsoft, it uses the Access Jet Engine to store data in its proprietary format. It allows importing and linking data from other databases.
2. MySQL: An open-source DBMS, widely popular.
3. Oracle: An object-relational database management system.
4. Microsoft SQL Server: Developed by Microsoft, it stores and retrieves data as requested by applications, whether local or across a network.
5. FileMaker: Initially an MS-DOS program, it’s now a cross-platform relational DBMS.

Database Terminology

1. Rows: Represent records.
2. Columns: These are vertical and alphabetically labelled.
3. Fields: Consist of related characters in a file.
4. Characters: Single symbols in a file.
5. Records: Comprise-related fields treated as a single entity.

USING MS – ACCESS TO THE DATABASE

To establish a computer-based database with MS Access.

Initiating MS Access involves the following steps:

1. Open the Start Menu.
2. Navigate to All Programs.
3. Find Microsoft Office.
4. Click on Microsoft Office Access.

Creating a Database

1. From the displayed window, select “blank database.”
2. On the right-hand side of the window, where the arrow is indicated in the image, click inside the file name text box and enter the desired database name.
3. Click the “Create” command button. This action will generate a database with the provided filename.

Creating a File

1. Click on the “Create” menu and choose “Table.”
2. In the “All Tables” tab, right-click on any of the tables.
3. Select “Design View.”

In the “Save As” dialog box, input the desired table name (e.g., Student Table) in the “Table Name” text box and confirm by clicking “OK.”

Database tables on a computer are structured with rows and columns. An MS Access table is organized into rows and columns, similar to the presented screen.

Each row holds records or different fields, determining the number of records in the table. In the example screen, the student table contains six records.

Columns usually represent fields within a database table, specifying the type of information stored. The shown screen includes three fields (data fields): REG. No., Surname, and First Name.

Creating Fields with Data Types

Fields are designated names relevant to the stored information. These field names are assigned data types, which govern the type of data they can accept. For instance, in the MS Access table above, the “Surname” field only accepts alphabetic characters, not numeric inputs like 10 or 500 as surnames.

To set the data type for a field in MS Access, follow these steps:

1. In the design view of the created table, input the field name under the “Field Name” tab.
2. Under the “Data Type” tab next to the field name, click the dropdown menu and choose “AutoNumber,” as depicted below.

In the provided screen, the field “ID Number” would be assigned the “Number” data type, considering its numeric nature. Similarly, the “Surname” and “First Name” fields would both be assigned the “Text” data type.

Unique Identifier

A table incorporates a unique identifier, often referred to as a KEY. In MS Access, the initial field is usually set as the default primary key. To designate another field as the primary key, right-click the respective cell and select “Primary Key.”

Note: The key symbol should appear beside the field after setting it as the unique identifier. If it doesn’t appear, repeat the prior steps.

Creating a Database

In general, creating a database using any DBMS involves the following fundamental steps..

1. Define the Database Structure

The structure specifies the preferred database organization. For a relational form, this includes RDBMS, table structure, row and column count, keys, and relationships.

2. Specify Field Types

When crafting a database, each field must accept a specific type of input, known as a data type. This prevents incorrect input, ensuring database integrity. Data types may differ across DBMS, but they generally fall into categories like alphanumeric/text, numeric, date, boolean, memo, currency, AutoNumber, hyperlink, attachment, and OLE object.

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