Oracle_sql performance tuning

SQL performance tuning.

1.Change table as no logging.

1. ALTER TABLE t1 NOLOGGING;

From my experience, I had to migration data > 2million records.
Data was customer information (CIF) of credit cards.
This sql statement can change migration time from 4 hours to 30 minutes.
But you have to ensure that you dont want redo action.

2.Tuning SQL statement.

1. Use primary or unique index as criteria join.
2. Filter from bottom to upper.
3. Filter from left to right.

Refer: www.techonthenet.com