Re: Unique constraints and nulls

[John English]

On 15/05/2014 10:46, Dyre Tjeldvoll wrote:
Could you not do
DELETE FROM FOO WHERE A = ? AND ( B = ? OR B IS NULL )

Unfortunately not. If B is not null, it would also delete the corresponding A 
where B is null. For example:
   A = X, B = Y
   A = X, B = NULL
Your solution would delete both, but I want to delete ONLY the row with the 
matching value for B.

But thanks for trying!
--
John English