From: Erland Sommarskog on
Ronnie R (RonnieR(a) writes:
> Thanks Jay, that is clear. Thanks
> So in this final example....
> WHERE INDEX4='foo' AND INDEX2='bar'
> a index on INDEX1 with included columns (INDEX2,INDEX3,INDEX4) would
> likely be used, as INDEX1 part of the index is ignored, INDEX2 used,
> INDEX3 ignored, INDEX4 used. Would you agree?

No. First of all it is not that likely that the optimizer would
use this index at all, as it would have to scan the entire index
to find the rows. But if the optimizer would use the index, it would
of course evalaute all columns present in the index against the WHERE

Erland Sommarskog, SQL Server MVP, esquel(a)

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