SQL

http://ktbase.blogspot.com/2014/04/sql_7.html

http://www.sqlcourse.com/insert.html

http://beginner-sql-tutorial.com/sql-where-clause.htm

http://www.sql-ex.ru/learn_exercises.php

bujji143/kumar4

http://www.youtube.com/playlist?list=PL32BC9C878BA72085

http://www.quackit.com/sql/tutorial/sql_outer_join.cfm