A databases is a set of tables that hold information about related things. DATABASES MANAGEMENT SYSTEM(DBMS) programs are designed purely to manage databases. They do this more efficiently than spreadsheet programs, although they are less instinctive to learn.
Features of database programs include:
• Creation of a database file consisting of one or more database objects: table, queries, forms and reports
• Wizards that guide the user through the creation of queries, forms including a menu system or ‘switchboard’, and reports
• Importing data from a text file, a spreadsheet or s table on a web page
• Formatting options for forms, reports and their controls and contents, including font name, style and size, and text alignment
• Creation of graphs or charts from a table or query, often using a chart wizard
• Exporting a databases object as a spreadsheet, a text file or web page
• Datasheet
• Tables store data and can display them in a ‘DATASHEET’ view.
Database`s record and field
Each row of data represents a record, which is a set of data about one type of thing such as an individual person, object or transaction.
Each column contains a data field ( or attribute). A field holds a specific type of data about a characteristic of the subjects of the records. Each column must have unique name. The type of data in a field is often text, but may also be numeric, date\time or other types.
A relational Database
• A relational database is a relatively complex but highly efficient type of database. It contains a table for each ‘entity’(type of person, object or transaction) about which data are stored. The tables are linked by ‘relationships’, which consist of references in field in one table to unique identifying ( or ID) field in another table. An important validation check, known as ‘referential integrity’, ensures that references can be made only to records that exist.
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