What is an inner join, and an outer join ?

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Krishna
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What is an inner join, and an outer join ?

Post by Krishna » Sun Mar 29, 2009 11:36 pm

What is an inner join, and an outer join ?

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Krishna
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Joined: Fri Jan 27, 2006 7:50 am

Post by Krishna » Sun Mar 29, 2009 11:36 pm

Inner Join: combine information from two or more tables by comparing all values that meet the search criteria in the designated column or columns of on e table with all the clause in corresponding columns of the other table or tables. This kind of join which involve a match in both columns are called inner joins.

Outer join is one in which you want both matching and non matching rows to be returned. DB2 has no specific operator for outer joins, it can be simulated by combining a join and a correlated sub query with a UNION.

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