Subject | SELECT IN Optimization |
---|---|
Author | donjules2k |
Post date | 2004-10-15T07:03:42Z |
Hi,
I have a query where I use an IN clause, and in the plan I notice it
does an index lookup for each item in the IN clause. Why does it do
this rather than a single lookup and pick out all items listed?
Also, I notice It does a natural join on one of the tables yet the
fields being used are indexed. What it the best way to analyse this
and see how to build a better index?
Giulio
I have a query where I use an IN clause, and in the plan I notice it
does an index lookup for each item in the IN clause. Why does it do
this rather than a single lookup and pick out all items listed?
Also, I notice It does a natural join on one of the tables yet the
fields being used are indexed. What it the best way to analyse this
and see how to build a better index?
Giulio