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How to reduce the joins in sql querry


How to reduce the joins in sql querry

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jcb
jcb
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10 or more joins are not a problem.
Bad normalized/designed data structure and no properly indexed tables are.

Just try to outer join two big tables by no indexed columns or using implicit data type conversion and you ill fell the pain.
(inner) joining 10 huge (well designed) tables by (tunned) indexed columns ill run smoothly.
TheSQLGuru
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jcb (11/20/2013)

...(inner) joining 10 huge (well designed) tables by (tunned) indexed columns ill run smoothly.


Until you have some data value skew, in which case the probability of getting screwed increases with increasing numbers of joins

Best,
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
TheSQLGuru on googles mail service
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