How to write "not in ()" sql query using join

Question

Could some one please provide how to write following sql query using joins. I do not want use not in as well as if possible I would like to replace where condition as well.

SELECT d1.Short_Code FROM domain1 d1 WHERE d1.Short_Code NOT IN (   SELECT d2.Short_Code   FROM Domain2 d2 ) 

I am using SQL Server 2008

Answer 1

This article:

• NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL: SQL Server

may be if interest to you.

In a couple of words, this query:

SELECT  d1.short_code FROM    domain1 d1 LEFT JOIN         domain2 d2 ON      d2.short_code = d1.short_code WHERE   d2.short_code IS NULL 

will work but it is less efficient than a NOT NULL (or NOT EXISTS) construct.

You can also use this:

SELECT  short_code FROM    domain1 EXCEPT SELECT  short_code FROM    domain2 

This is using neither NOT IN nor WHERE (and even no joins!), but this will remove all duplicates on domain1.short_code if any.