Now let’s add a table-level CHECK constraint. Select the Check Existing Data on Creation or Enabling option.ĭisable the constraint when new data is added to the table or when existing data is updated in the table.Ĭlear the Enforce Constraint for INSERTs and UPDATEs option.ĭisable the constraint when a replication agent inserts or updates data in your table.Ĭlear the Enforce For Replication option. This is referred to as a column-level constraint, because it is defined on a single column. Type the new expression in the Expression field.

ADD CONSTRAINT CHKPersonAge CHECK (Age>18 AND. ADD CHECK (Age>18) To allow naming of a CHECK constraint, and for defining a CHECK constraint on multiple columns, use the following SQL syntax: ALTER TABLE Persons. In the Check Constraints dialog box, under Selected Check Constraint, select the constraint you wish to edit.Ĭomplete an action from the following table: To To create a CHECK constraint on the 'Age' column when the table is already created, use the following SQL: ALTER TABLE Persons. It limits the values that a column can hold in a relation. On the Table Designer menu, click Check Constraints. Check Constraint is used to specify a predicate that every tuple must satisfy in a given relation. In the Object Explorer, right-click the table containing the check constraint and select Design. Using SQL Server Management Studio To modify a check constraint You can modify a check constraint in SQL Server by using SQL Server Management Studio or Transact-SQL when you want to change the constraint expression or the options that enable or disable the constraint for specific conditions.

Tableplus check constraint