Oracle Sql Queries

http://www.orafaq.com/wiki/SQL_FAQ

http://philip.greenspun.com/sql/complex-queries.html

http://it.toolbox.com/blogs/oracle-guide/learn-oracle-the-index-10395

http://cisnet.baruch.cuny.edu/holowczak/oracle/sqlplus/

http://oracle-dba-online.com/sql/oracle_sql_tutorial.htm

http://download.oracle.com/docs/html/A95915_01/sqcmd.htm

http://www.oracle-base.com/articles/misc/UNIXForDBAs.php

http://ss64.com/ora/ (VERY GOOD ONE)

http://www.databasejournal.com/features/oracle/article.php/3523296/Strong-SQL-Made-Even-Stronger-Oracle-10g-SQL-Enhancements-Part-1.htm

http://www.dba-oracle.com/unix_linux/common_commands.htm

http://www.bijoos.com/oracle/unix4dba1.htm (Best one for Unix Commands which use for DBA)

http://www.dba-oracle.com/Shell-Script-sec.pdf 

http://www.idevelopment.info/cgi/ORACLE_dba_scripts.cgi

http://www.techonthenet.com/oracle/  (PL/SQL)