Deleting a Column from a Key

Maintaining Tables with Related Constraints › Impact of Changing Structure Definitions on Constraints › Deleting a Column from a Key

Deleting a Column from a Key

If you delete a column from a key, the result varies depending on the type of constraint. This action has no effect on Check constraints. However, Foreign and Unique constraints cannot be updated in this way.

Type of Constraint	Effect on Constraint
Check	Not applicable.
Foreign and Unique	This action is not allowed because the rebind recreates the key as before resulting in a new KEY since the source of the constraints reflects the old column list. CA Datacom Datadictionary generates a DSF return code CON when you attempt to delete a column from a key defined with these constraints. Drop the constraint before deleting the column from the key.

Type of
Constraint

Effect on Constraint

Check

Not applicable.

Foreign and
Unique

This action is not allowed because the rebind recreates the key as before resulting in a new KEY since the source of the constraints reflects the old column list.

CA Datacom Datadictionary generates a DSF return code CON when you attempt to delete a column from a key defined with these constraints. Drop the constraint before deleting the column from the key.