Components of a Database System
A complete database system is more than just tables. It combines several components so that ordinary users can use it easily:
- Tables — where the actual data is stored.
- Forms — a user-friendly interface for entering and editing data.
- Queries — used to search and filter information.
- Reports — a neat, organised display or printout for reading or printing.
Key idea
Forms are for entering data, queries are for finding data, and reports are for presenting results. The data itself is stored in tables.
Forms and Reports
A form makes data entry easier and reduces errors, because the user simply fills in the provided spaces. Validation on a form, such as ensuring an age is a positive number, helps prevent incorrect data. A report takes data from tables or queries and presents it in a neat format for reading or printing, for example a student attendance list.
Example
In a school library system: a librarian uses a form to register new books, a query to find overdue books, and a report to print the monthly list of fines.
Testing the System
Testing is carried out to detect errors and make sure the system works as intended before real use. Programmers use different types of test data: normal data (typical values), boundary data (values at the edge of the allowed range) and invalid data (values that should be rejected).
Remember
Tables store data, forms enter data, queries find data, reports display data. Always test with normal, boundary and invalid data.