Hi, thanks for this post,

i have a question , can i create an incremental variable and make it at the place of -255 in this script:

SELECT f.father_id, f.father_name, s.father_id as son_id, s.paternity

from [dbo].[father] f

INNER JOIN [dbo].[son] s

on isnull(s.father_id, -255)=f.father_id

GO

so this column will be a unique column,

thx in advance