I need a little help in my SQL queries i'm not really sure whether this can be done ...
I have 3 tables T1,T2,T3
T1 - contains the id and phone_num
T2 - contains the id only
T3 - contains a list of phone numbers
I compare T2 with T1 to obtain the phone_num that are in T2 using this statement..
SELECT T1.case_id, T1.phone_no FROM T1 LEFT OUTER JOIN T2 ON T1.case_id = T2.case_id WHERE T2.case_id = T1.case_id
but now i want to use that result that i obtain ie the phone_num to compare it to T3 which have a whole list of phone numbers. i want to obtain the list of numbers that does not match the phone_num i previously obtain using the SQL query above.
I'm a bit confused of how to use the result i previously obtained ..and i'm not really sure whether this is possible or not.. is it possible to provide me with an example..