Domain characteristics
You define the domain characteristics of columns when you create
a table. A column can contain the following domain characteristics:
- Data type (INTEGER, CHAR, DATE, and so on)
- Format (for example, yy/mm/dd)
- Range (for example, 1,000 to 5,400)
- Meaning (for example, serial number)
- Allowable values (for example, only grades S or U)
- Uniqueness
- Null support
- Default value
- Referential constraints
For information about how to define domains, see Select data types. For information about how to create your tables and database, see Implement a relational data model.