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differernce between outer and inner joins

Posted: Mon Jun 06, 2005 1:50 am
by bugthefixer
I wonder if anybody could help me with inner and outer joins, what is the exact difference

Posted: Mon Jun 06, 2005 2:12 am
by timvw
I'll give an example:

tableA:
(1, tim)
(2, mike)
(3, john)

tableB:
(1, van wassenhove)
(2, myers)
(4, doe)


tableA INNER JOIN tableB USING id
(1, tim, van wassenhove)
(2, mike, myers)

tableA LEFT OUTER JOIN tableB USING id
(1, tim, van wassenhove)
(2, mike, myers)
(3, john, NULL)

tableA RIGHT OUTER JOIN tableB USING id
(1, tim, van wassenhove)
(2, mike, myers)
(4, NULL, doe)

tableA FULL OUTER JOIN tableB USING id
(1, tim, van wassenhove)
(2, mike, myers)
(3, john, NULL)
(4, NULL, doe)