Usefull Links

 Data Pump

http://docs.oracle.com/cd/B28359_01/server.111/b28319/dp_import.htm#g1025464

Advanced User-Managed Recovery Scenarios

http://docs.oracle.com/cd/B19306_01/backup.102/b14191/recoscen.htm#BRADV018

SQL Trace and TKPROF utillity

http://docs.oracle.com/cd/B10500_01/server.920/a96533/sqltrace.htm

To Generate ASH report

http://www.techdoubts.com/how-to-generate-ash-report/

Interview Questions

https://rajeevjhaoracle.wordpress.com/category/interview-questions/

Listner

http://www.in-oracle.com/Oracle-DBA/architecture/oracle-listener.php#1

DBA scripts

https://oracle-base.com/dba/scripts

blogs
http://oracleinaction.com/