SQL: Performance comparison for exclusion (Join vs Not in)

Question

I am curious on the most efficient way to query exclusion on sql. E.g. There are 2 tables (tableA and tableB) which can be joined on 1 column (col1). I want to display the d

Answer 1

The questions has been asked several times. The often fastest way is to do this:

SELECT * FROM table1 
WHERE id in (SELECT id FROM table1 EXCEPT SELECT id FROM table2)

As the whole joining can be done on indexes, where using NOT IN it generally cannot.