Help W/Disabling FK Constraints for Batch Operations

HI all,

I'm trying to have a SProc that will initialize a database for me. This db is in development (I'm primarily writing SSIS packages, atm), and I constantly need to truncate the tables, then re-add a dummy/unknown row (PK/Identity value = 1). Of course, I need triggers not to fire (got that part working), and FK constraints to be bypassed temporarily -- that's the problem.

Here's where I'm at:

-
CREATE PROCEDURE [dbo].[_InitializeDB]
AS

SET NOCOUNT ON

DECLARE @.name varchar(255)
DECLARE @.sql nvarchar(255)

DECLARE tables CURSOR FOR SELECT [name] FROM [sysobjects] WHERE [type]='U' AND [name]<>'sysdiagrams'

OPEN tables
FETCH NEXT FROM tables INTO @.name
WHILE @.@.FETCH_STATUS=0
BEGIN
SET @.sql = 'ALTER TABLE ['+ @.name + '] NOCHECK CONSTRAINT ALL'
EXEC sp_executeSQL @.sql
SET @.sql = 'DISABLE TRIGGER ALL ON [' + @.name + ']'
EXEC sp_executeSQL @.sql
SET @.sql = 'TRUNCATE TABLE [' + @.name + ']'
EXEC sp_executesql @.sql
BEGIN TRY
SET @.sql = 'INSERT INTO [' + @.name + '] (Active) VALUES (0)'
EXEC sp_executeSQL @.sql
END TRY
BEGIN CATCH
PRINT @.sql + ':'
PRINT ERROR_MESSAGE()
END CATCH
SET @.sql = 'ENABLE TRIGGER ALL ON [' + @.name + ']'
EXEC sp_executeSQL @.sql
SET @.sql = 'ALTER TABLE ['+ @.name + '] CHECK CONSTRAINT ALL'
EXEC sp_executeSQL @.sql
FETCH NEXT FROM tables INTO @.name
END

CLOSE tables
DEALLOCATE tables
-

Running this Sproc produces (for the first ref'd table):

Msg 4712, Level 16, State 1, Line 1
Cannot truncate table 'Person' because it is being referenced by a FOREIGN KEY constraint.

If you dont wanna be bothered by the FK Constraints you have to drop them do your work and recreate them after you did your work.

HTH, Jens Suessmeyer.

http://www.sqlserver2005.de

|||TRUNCATE TABLE doesn't check the state of the FK constraint so this method will not work. You will have to drop and recreate the FK constraint for the truncate table to work.