These procedures are very useful when you need to load bulk data and you know the data is correct -- but you do not need the foreign keys and check constraints to interfere. You might also use them when you want to change key values and don't want the constraints to get in your way.
So, the following procedure will disable/enable all constraints for a given parametric table:
CREATE PROCEDURE sp_ConstraintState @TblName VARCHAR(128), @State BIT = 1 AS DECLARE @SQLState VARCHAR(500) IF @State = 0 BEGIN SET @SQLState = 'ALTER TABLE '+ @TblName + ' NOCHECK CONSTRAINT ALL' END ELSE BEGIN SET @SQLState = 'ALTER TABLE ' + @TblName + ' CHECK CONSTRAINT ALL' END EXEC (@SQLState) go
exec sp_ConstraintState 'products',0
...will disable all constraints on the products table in the Northwind database.
The following procedure will use sp_constraintState to disable all constraints in the database:
Create proc sp_disable_all_const_in_db as 'exec sp_MsForEachTable 'sp_ConstraintState ''?'',0 go
For example, to disbale all constraints in the database:
About the author
Eli Leiba works at the Israel Electric Company as a senior application DBA in Oracle and Microsoft SQL Server. He has certifications from Microsoft and BrainBench in Oracle and SQL Server database administration and implementation. Mr. Leiba holds a B.S. in computer science and has 11 years of experience working in the database field. Additionally, Mr. Leiba teaches SQL Server DBA and development courses at the Microsoft CTEC and serves as a senior database consultant for several Israeli start-up companies.
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