Foreign key DROP/CREATE generator - 2005

IF OBJECT_ID (N'dbo.GetFieldsConcat', N'FN') IS NOT NULL
DROP FUNCTION dbo.GetFieldsConcat;
GO
CREATE FUNCTION dbo.GetFieldsConcat (@objectName sysname, @foreignKeyName sysname, @isParent bit)
RETURNS varchar(max)
WITH EXECUTE AS CALLER
AS
BEGIN
DECLARE @theFields varchar(max)
SET @theFields = ''
SELECT @theFields = @theFields + '[' + CASE WHEN @isParent = 1 THEN pc.name ELSE cc.name END + '],'
FROM sys.foreign_keys fk
INNER JOIN sys.schemas fks ON fks.schema_id = fk.schema_id
INNER JOIN sys.objects oc ON fk.parent_object_id = oc.object_id
INNER JOIN sys.schemas cs ON cs.schema_id = oc.schema_id
INNER JOIN sys.objects op ON fk.referenced_object_id = op.object_id
INNER JOIN sys.schemas ps ON ps.schema_id = op.schema_id
INNER JOIN sys.foreign_key_columns pfkc ON pfkc.constraint_object_id = fk.object_id
INNER JOIN sys.columns pc ON pc.column_id = pfkc.referenced_column_id AND pc.object_id = fk.referenced_object_id
INNER JOIN sys.columns cc ON cc.column_id = pfkc.parent_column_id AND cc.object_id = fk.parent_object_id
WHERE ((@isParent = 1 AND op.name = @objectName) OR (@isParent = 0 AND oc.name = @objectName))
AND fk.name = @foreignKeyName
IF LEN(@theFields) > 0
SET @theFields = LEFT(@theFields, LEN(@theFields) - 1)
RETURN(@theFields)
END;
GO


DECLARE @TableName sysname
SET @TableName = 'tbl_stockable_type'
SELECT 'IF EXISTS (SELECT * FROM sys.foreign_keys WHERE object_id = OBJECT_ID(N''[' + fks.name + '].[' + fk.name + ']'') AND parent_object_id = OBJECT_ID(N''[' + cs.name + '].[' + oc.name + ']''))' + CHAR(13) + CHAR(10) +
'ALTER TABLE [' + cs.name + '].[' + oc.name + '] DROP CONSTRAINT [' + fk.name + ']'
FROM sys.foreign_keys fk
INNER JOIN sys.schemas fks ON fks.schema_id = fk.schema_id
INNER JOIN sys.objects oc ON fk.parent_object_id = oc.object_id
INNER JOIN sys.objects op ON fk.referenced_object_id = op.object_id
INNER JOIN sys.schemas cs ON cs.schema_id = oc.schema_id
WHERE op.name = @TableName
UNION ALL
SELECT 'ALTER TABLE [' + cs.name + '].[' + oc.name + '] WITH NOCHECK ADD CONSTRAINT [' + fk.name + '] FOREIGN KEY(' + dbo.GetFieldsConcat(oc.name, fk.name, 0) + ')' + CHAR(13) + CHAR(10)
+ 'REFERENCES [' + ps.name + '].[' + op.name + '] (' + dbo.GetFieldsConcat(op.name, fk.name, 1) + ')'
FROM sys.foreign_keys fk
INNER JOIN sys.schemas fks ON fks.schema_id = fk.schema_id
INNER JOIN sys.objects oc ON fk.parent_object_id = oc.object_id
INNER JOIN sys.schemas cs ON cs.schema_id = oc.schema_id
INNER JOIN sys.objects op ON fk.referenced_object_id = op.object_id
INNER JOIN sys.schemas ps ON ps.schema_id = op.schema_id
WHERE op.name = @TableName