Question

I have a requirement.

I have two tables say TableA and TableB. Both having a column called “rec_id”. My requirement is to get the maximum of the values contained in these two columns using a single query.

eg: In TableA, I have “rec_id” values as {1,5,6} and in TableB, I have “rec_id” values as {1,4,2}. So after executing the query, I want “6” as the result since 6 is the maximum value from these two columns, out of these two tables.

Thanks in Advance,
Anish Kurian

Answer 1

select max(rec_id) from 
(
  (select rec_id from tablea)
 union all
  (select rec_id from tableb)
) combined