Creating a Check Constraint

Creating a check constraint specifies a condition that any value must pass before it is inserted into the table.

A check constraint specifies a condition that any value must pass before it is inserted into the table. You can create a check constraint at the table or column level. Column-level check constraints reference a single column. Table-level check constraints apply to the entire table.

  1. In the left pane of the Administration Console, expand ASE Servers > Schema Objects > Tables, then choose one of the following:
    • User Tables
    • Proxy Tables
  2. Click the Name field of the table, then click the drop-down arrow and select Properties.
  3. In the left pane, click Check Constraint.
  4. Select New.
  5. On the Name screen, enter a name for the check constraint.
  6. On the Expression screen, enter an expression that defines the constraint.
    For example, salary > 0. The comparable command line syntax using alter table is:
    alter table sample.dbo.employee
    add constraint test_const
    CHECK  (salary > 0)
  7. (Optional) Click Summary to review the check constraint expression.
  8. Click Finish .
Related tasks
Creating a Unique Constraint or Primary Key
Creating a Foreign Key
Binding Defaults and Rules to a Column