Bookmark, Explain Plan understanding

When I display my execution plan, a node indicates an Index Seek, the object
listed is the name of the nonclustered indexe used, and the Output list has
[Bmk1002]. Normally in the Output list I see a list of columns when there is
a Bookmark involved, but this is confusing to me cause it is an Index Seek
and the Output list is simply [Bmk1002]. Using "set showplan_all on" shows
the same thing. In this instance do I look at the corresponding Bookmark node
to determine which columns are being sought? Why does it give me a Bookmark
when I am having returned an Index Seek? This is a nasty multi-join query so
I am not including the statement or the tables and indexes. Any possible
explanations would be appreciated.
--
Message posted via http://www.sqlmonster.comWell, it is because you are trying to get the column/s that do not covered
by index and SQL Server is using nonclusterd index to point to datapage to
return the data
Like
select col1, col30 from table where col1=5
col1 has an index and we will see index seek with bookmark because col30
does not have any index in that case
"cbrichards via SQLMonster.com" <u3288@.uwe> wrote in message
news:605b4028efd9b@.uwe...
> When I display my execution plan, a node indicates an Index Seek, the
> object
> listed is the name of the nonclustered indexe used, and the Output list
> has
> [Bmk1002]. Normally in the Output list I see a list of columns when there
> is
> a Bookmark involved, but this is confusing to me cause it is an Index Seek
> and the Output list is simply [Bmk1002]. Using "set showplan_all on" shows
> the same thing. In this instance do I look at the corresponding Bookmark
> node
> to determine which columns are being sought? Why does it give me a
> Bookmark
> when I am having returned an Index Seek? This is a nasty multi-join query
> so
> I am not including the statement or the tables and indexes. Any possible
> explanations would be appreciated.
> --
> Message posted via http://www.sqlmonster.comsql