November 4, 2008 at 11:48 pm
balbirsinghsodhi (11/4/2008)
Hi Gail..Here is the attached actual execution plan.
Thanks. I'll take a look at it later in the week. I've got a lot of things to get done in the next 2 days.
Thanks again for helping me. what are the main thing to consider in the query execution plan. ?
There's no one main thing. What you're looking for is appropriate operators (index seeks as much as possible, joins appropriate to the number of rows, etc), estimated and actual row counts similar and the costs spread evently across the query. Note that if the row estimates are wrong, the costs will be wrong as well.
sometimes I see that there is a proper index on the table but it is still taking index scan. for example in the execution plan there is transac_live table using an index scan . I don't know why it's taking index scan, table is already indexed.
It means the index isn't appropriate (doesn't have the columns in the right order or doesn't have enough columns) or the conditions in the where clause aren't sargable (able to be used as a search argument)
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
November 4, 2008 at 11:52 pm
balbirsinghsodhi (11/4/2008)
I think it's not a bad idea to start some kind of web site and help people by charging some money.
What, like this one? Except of course SSC doesn't charge for advice.
To do performance tuning properly (and I'm also a consultant in that field) requires one to sit down with the database that's giving problems and examine it in detail, looking at the hardware, the queries, the tables, some management views and then applying experience to that. It's not the kind of thing that can be done easily across the web.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
November 5, 2008 at 4:59 am
GilaMonster (11/4/2008)
balbirsinghsodhi (11/4/2008)
I think it's not a bad idea to start some kind of web site and help people by charging some money.What, like this one? Except of course SSC doesn't charge for advice.
To do performance tuning properly (and I'm also a consultant in that field) requires one to sit down with the database that's giving problems and examine it in detail, looking at the hardware, the queries, the tables, some management views and then applying experience to that. It's not the kind of thing that can be done easily across the web.
Actually the TUNING part can be easily done across the web provided the client has a VPN into their network and the consultant has a high-speed internet connection. I too am a SQL Server consultant with a large part of my business revolving around relational engine performance issues but I work from home 75% of the time. I will only take on new long-term clients if they can agree to that constraint. My wife is a doctor and we have a 3 year old daughter so I have to be home the nights she is on call (2 on-2 off schedule) or find and overnight sitter.
What CANNOT be easily done "over-the-net" is the mentoring that I spoke of where the consultant provides knowledge/experience transfer to the local staff. Live Meeting and other products are great, but they only go so far.
Best,
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
TheSQLGuru on googles mail service
Viewing 3 posts - 31 through 32 (of 32 total)
You must be logged in to reply to this topic. Login to reply