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Old 02-07-12, 16:42
rav_neni rav_neni is offline
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Index on Foreign Key with NULL

Hi,
We have a fact table with foreign key and this foreign key is joined to lookup table to get descriptions. I have added index on this foreign key to improve the join performance, but it is not performing better.

Are there any types of indexes suited for foreign keys with nulls?

Thanks
Rav
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Old 02-07-12, 17:41
r937 r937 is offline
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performance is an attribute of a query, not of an index

whether or not an index is used depends on the query
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