Most CPU consuming SQL Queries in Oracle.
Step 1: you need to find out the SID of the session which is consuming highest CPU with the following query
Step 2: For that SID you can find out the sql hash value from v$session on which sql query its working. From that sql hash value you can get the sql_text from v$sqlarea view. It will provide you the completed sql query executing by the session.
(select sql_hash_value from v$session where SID = ’28’)