Performance Tuning Tips

· Never Use the functions and calculations on Indexed Columns. 
· Sequence and Hard coded values can be at any place in 11g 
· Use the Indexed columns should be in Sequence
· Cost of the entire Query should be minimum
· Should not allow the Full Scan of a table 
· Use Exists/ Not Exists Instead of In and Not In 
· Use of Union All instead of Union 
· Use Bulk Collects for large volume of data for Inserting and Updating 
· Create Indexes for the custom tables 
· Gather Statistics 
· Performing Explain Plan, TK Prof