In the Table Designer category, you can set when the constraint is enforced. In the Identity category, you can change the name of the check constraint and add a description (extended property) for the constraint.

Make sure to enclose any non-numeric constraint values in single quotation marks ('). Or, to require entries in the zip column to be five digits, type: zip LIKE '' For example, to limit the entries in the SellEndDate column of the Product table to a value that is either greater than or equal to the date in the SellStartDate column or is a NULL value, type: SellEndDate >= SellStartDate OR SellEndDate IS NULL In the Check Constraint Expression dialog box, type the SQL expressions for the check constraint.

In the Check Constraints dialog box, select in the Expression field and then select the ellipses (.). In Object Explorer, expand the table to which you want to add a check constraint, right-click Constraints and select New Constraint. Use SQL Server Management Studio Create a new check constraint To query existing check constraints, use the sys.check_constraints system catalog view. For more information on adding column constraints, see ALTER TABLE column_constraint.įor more information, see Unique Constraints and Check Constraints. You can create a check constraint in a table to specify the data values that are acceptable in one or more columns in SQL Server by using SQL Server Management Studio or Transact-SQL.

Tableplus check constraint