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This is documentation for Caché & Ensemble. See the InterSystems IRIS version of this content.

For information on migrating to InterSystems IRIS, see How to Migrate to InterSystems IRIS, available on the WRC Distributions page (login required).


Suppress/return error upon ADD a foreign key, when a key of that name already exists.


[SQL]    DDLNo311=n


The value n may be 1 or 0:

  • If 1 (true) when an attempt is made to ADD a foreign key, even if a key of that name already exists, Caché suppresses the SQLCODE -311 error.

  • If 0 (false) Caché returns the error.



Range of Values

0 or 1. The default is 0.

Management Portal

On the page System Administration > Configuration > SQL and Object Settings > General SQL Settings, for the Allow DDL ADD Foreign Key Constraint when Foreign Key Exists setting, choose Yes (true) or No (false).