Question

I don’t know much about SQL at all, but I have a table and it has a unique key constraint which I can see in SSMS by expanding the Keys folder under my table. It makes one column, ‘name’, UNIQUE.

At the moment it’s completely unique, but I need to change it so name is unique for a specific ID in another column, ‘catflapID’. So names can be duplicated in the table but for each catflapID there can be no duplicates.

I know absolutely nothing of how to do this, and I need somehow to end up with a script that removes the existing constraint and adds my new constraint.

Any advice?

Answer 1

IF  EXISTS (SELECT * FROM sys.indexes WHERE object_id = OBJECT_ID(N'[dbo].[test_table]') AND name = N'IX_test_table')
ALTER TABLE [dbo].[test_table] DROP CONSTRAINT [IX_test_table]
GO

ALTER TABLE [dbo].[test_table] ADD  CONSTRAINT [IX_test_table] UNIQUE NONCLUSTERED 
(
    [c_name] ASC,
    [c_id] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
GO