November 20, 2014 at 10:14 pm
Hello Everyone,
How index helps for join in sql server ? when we join two tables how the index took place, in which manner it executes the query? is there any links to read out to understand this ?
I understand how the where clause works, by the this video..
Is there any other video or article link to understand about join vs index
November 21, 2014 at 1:25 am
One of the first results on Google for "sql server join index":
(it is written for SQL Server 2000 though, but a lot will probably still be applicable.)
You should try Google sometimes, it's really amazing.
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November 22, 2014 at 9:14 am
Effectively, the use of an index in the ON clause is the same as the use of an index in the WHERE clause. The criteria can act as a filter and can take advantage of the statistics and the index storage as a means of accelerating access. In addition, having the index store the data in the same order that is needed by the query can help speed up joins in some cases. Also, for joins, look to making sure you have enforced (WITH CHECK) foreign keys in place. This is also taken into account by the optimizer.
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