Database Key Terms

Database Key Terms

1. Relational database- Tables connected together with primary and foreign keys

2. Table- Where data is stored

3. Foreign key- When the primary key appears in another table

4. Field- A column in a table with one piece of information E.g. In a title

5. Record- Row in a table which contains information about one person or things E.g. Criminal record

6. Flatfile table- Single tables not connected in any way

7. Composite Key- Its used to uniqually identify information, but it uses two or more fields

8. Query- It is a search to find information in the databse

9. Data Types-A particular type of data item, as defined by the value it can take E.g. Date, time, text

10. Validation Rule- Check the data is VALID and REASONABLE E.g. School students have to be between 11-16,so the computior will only allow these numbers

11. Entity Relationship Diagram (ERD)- Relationship between tables. Can be a 1 to many, 1 to 1, and Many to Many

12. Field length- Number of characters allowed to be entered in a field E.g. First Name = 30 characters

13. Input Mask- Controls entry into a field, E.g. _LL9 9LL

14. Data dictionary- A plan of a database tableand give details of the structure E.G. Field length, Validation Rules

15. Normalisation- Reducing data that is not required. Also seperating data into appropriate tables

16. Database- A story of data in a logical way

17. Primary Key- Used to uniqually identify data in a table E.g. Exam Number