|
Home > Archive > MS SQL Server > December 2006 > What is good and what is bad in the Graphical Exec Plan?
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
What is good and what is bad in the Graphical Exec Plan?
|
|
| ChrisR 2006-12-06, 7:12 pm |
| Howdy all. I'm looking at the Graphical Exec Plan on a sproc right now and I
see that 90% of the resources are going towards a Hash Match/ Right Outer
Join. How do I determine if that is good, bad, or indifferent?
TIA, ChrisR
| |
| Tracy McKibben 2006-12-06, 7:12 pm |
| ChrisR wrote:
> Howdy all. I'm looking at the Graphical Exec Plan on a sproc right now and I
> see that 90% of the resources are going towards a Hash Match/ Right Outer
> Join. How do I determine if that is good, bad, or indifferent?
>
> TIA, ChrisR
>
>
What are the two steps leading in to that join? If there is a table
scan or index scan leading in to that join, that might be an opportunity
to create a missing index, or improve an existing one.
--
Tracy McKibben
MCDBA
http://www.realsqlguy.com
| |
| ChrisR 2006-12-06, 7:12 pm |
| First a Select, than a Compute Scalar. Does this mean anything?
"Tracy McKibben" <tracy@realsqlguy.com> wrote in message
news:4576F995.80900@realsqlguy.com...
> ChrisR wrote:
and I[color=darkred]
Outer[color=darkred]
>
> What are the two steps leading in to that join? If there is a table
> scan or index scan leading in to that join, that might be an opportunity
> to create a missing index, or improve an existing one.
>
>
> --
> Tracy McKibben
> MCDBA
> http://www.realsqlguy.com
| |
| Aaron Bertrand [SQL Server MVP] 2006-12-06, 7:12 pm |
| Can you hover over that node in the plan and tell us more information about
it? All of the "Estimated" values would be a good start.
Remember, 90% of a very, very, very fast and efficient query is negligible.
It's when it's a very slow or intensive query that 90% becomes a worthwhile
target for optimization.
So, going by the execution plan (especially estimated only) is never enough
information. You should run the query with execution plan, statistics i/o,
client statistics etc. all running, and see if anything jumps out at you
then.
"ChrisR" < noFudgingWay@NoEmail
.com> wrote in message
news:%232X%23TdVGHHA
.4588@TK2MSFTNGP05.phx.gbl...
> Howdy all. I'm looking at the Graphical Exec Plan on a sproc right now and
> I
> see that 90% of the resources are going towards a Hash Match/ Right Outer
> Join. How do I determine if that is good, bad, or indifferent?
>
> TIA, ChrisR
>
>
| |
| Tracy McKibben 2006-12-06, 7:12 pm |
| ChrisR wrote:
> First a Select, than a Compute Scalar. Does this mean anything?
>
Not offhand, no... Maybe post the query?
--
Tracy McKibben
MCDBA
http://www.realsqlguy.com
|
|
|
|
|