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Checks Collection

This feature will be removed in a future version of Microsoft SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature.

The Checks collection contains Check objects that expose Microsoft SQL Server integrity constraints defined on the columns of a table.

SQL-DMO object model that shows the current object

Remarks

With the Checks collection, you can:

  • Define an integrity constraint on a SQL Server column.

  • Remove an existing constraint from a SQL Server column.

SQL Server integrity constraints can be defined as part of a CREATE TABLE or ALTER TABLE statement.

When creating a SQL Server table using the Table object, an empty Checks collection is created as part of the Table object creation. Adding Check objects to the Checks collection adds constraint definition text to the CREATE TABLE statement generated when the Table object is added to the Tables collection of a Database object.

If a Table object references an existing SQL Server table, changes to the Checks collection generate ALTER TABLE statements.

For more information about creating integrity constraints, see Check Object.

To remove a CHECK constraint

  1. Get the desired Table object from the Tables collection of a Database object.

  2. Use the BeginAlter method of the Table object to mark the beginning of changes to the SQL Server table.

  3. Use the Remove method of the Checks collection of a Table object. Indicate the targeted integrity constraint using the constraint name or the ordinal location in the collection, as in:

    oTables("Order Details").Checks.Remove("CK_Order Details_Discount")

  4. Use the DoAlter method of the Table object to submit the changed table definition to SQL Server.