Why and How to perform a session tracing in Oracle ?

  Why ?

In oracle in certain cases you will need to trace the session and see the details of where and how it is work and see all details of error if any, this is trace and it is level.

How ?

Below are some knowledge article from oracle that I used to reach this matter :

1-      First :

How to Enable SQL_TRACE for Another Session or in MTS Using Oradebug (Doc ID 1058210.6)

2- Second  :

How To Collect 10046 Trace (SQL_TRACE) Diagnostics for Performance Issues (Doc ID 376442.1)

3- Third

How to Trace a Procedure From Active Session And View All Statements and Continually Track All or Some of the Statements Using 10046 Tracing (Doc ID 2412465.1)