Simple steps to do explain plan - Performance Tuning

 

For my reference:

1.        Set autotrace on
2.        Set autotiming on
3.        Explain plan for select * from pa_projects_all
4.        It will display elapsed time; to open the trace file write following command
5.        Select * from table(dbms_xplan.display);
6.        Trace file will be diplayed; Analyze the cost and the indexes used in table
7.        To do fine tuning we use HINTS (search in google Ex: /*+ all_rows*/   etc..
8.        Use hints before columns (Ex: Explain plan for select /*+all_rows*/ project_id,segment1,creation_date from pa_projects_all) 
9.        Search in web : Index – Hint, Bitmap Index, Optimization (Cost based, Rule Based)…etc…