Included columns in index.. performance implications ?

How detrimental is it to create multiple indexes that have included columns
as opposed to creating composite indexes that include that all those columns
?
I want to add the index with included columns but also concerned about
slowness in performance on writes. Either way I want to create the index..
the only difference will be whether I decide to have those included columns
or not..
Thanks
It is not really a performance decision. It depends if those columns will be
used, for example, on the WHERE clause or just on the SELECT clause. If these
columns will be listed only in the SELECT clause then use included columns.
If you are going to use those columns as a search criteria then included
columns would not help.
Regarding performance, include columns are better because they are only
stored at the leaf level of the index.
Hope this helps,
Ben Nevarez
Senior Database Administrator
AIG SunAmerica
"Hassan" wrote:

> How detrimental is it to create multiple indexes that have included columns
> as opposed to creating composite indexes that include that all those columns
> ?
> I want to add the index with included columns but also concerned about
> slowness in performance on writes. Either way I want to create the index..
> the only difference will be whether I decide to have those included columns
> or not..
> Thanks
>