Please note : This help page is for an older version of Enteprise Archtiect. The latest help can be found here.

Check Constraints

A Check Constraint enforces domain integrity by limiting the values that are accepted by a column.

Access Tools | Database Builder | Click on Table name > Constraints | Right-click | Add New Constraint (Ctrl+N)

In diagram or Project Browser | Right-click on Table | Features & Properties | Operations > Constraint | Add New Constraint (Ctrl+N)

Create a Constraint

Step

Action

See also

1

On the 'Constraint' tab of the Columns and Constraints screen, a new constraint is automatically created and assigned the default constraint name and a 'Type' of index.

Overtype the constraint name with a name that identifies the constraint as a check constraint, such as 'CHK_ColumnName' (the CHK_ prefix is optional).

Database Table Constraints

2

In the 'Type' field, change the value from 'index' to 'check'.

3

In Properties panel, for the Condition property type in the SQL statement that will be used as the Check Condition; for example, column1 < 1000.

If the condition is long, click on the button to display a SQL editor (with syntax highlighting).

Delete a Check Constraint

If you do not want to keep a check constraint, either:

  • Right-click on it in the list and select Delete constraint '<name>', or
  • Click on the item and press Ctrl+D

The constraint is immediately deleted.

Learning Center topics

  • Alt+F1 | Enterprise Architect | Database Engineering | Physical Data Model | Check Constraint