SQL Server - NOT IN

Question

I need to build a query that will show me records that are in Table 1, but that are not in Table 2, based on the make-model-serial number combination.

I know for fac

Answer 1

It's because of the way NOT IN works.

To avoid these headaches (and for a faster query in many cases), I always prefer NOT EXISTS:

SELECT  *  
FROM Table1 t1 
WHERE NOT EXISTS (
    SELECT * 
    FROM Table2 t2 
    WHERE t1.MAKE = t2.MAKE
    AND   t1.MODEL = t2.MODEL
    AND   t1.[Serial Number] = t2.[serial number]);