More about EXISTS and IN

This is a very useful link that will definitely answer your questions regarding whether to use EXISTS or IN on your SQL statements.


http://asktom.oracle.com/pls/asktom/f?p=100:11:3263397840860471::::P11_QUESTION_ID:953229842074

Basically the rule of thumb is:

Small query, large subquery = EXISTS
Large query, small subquery = IN
Large query, large subquery = either