Interpreting the Estimated Execution Plan

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

From: Sky Fly (nobody_at_blackhole.com)
Date: 04/21/04 

Date: Wed, 21 Apr 2004 12:12:47 +0100

Hello,

I'm trying to improve the performance of a query, and one
of the tools I'm turning to in this regard is the Estimated
Execution Plan shown in Query Analyzer. I have the following
questions:

1. I notice that each of the icons shown in the plan has a
'cost' associated with it, which is expressed as a percentage
and is shown in a label that you can see if you move the mouse
over the icon. If an icon has a high cost, does it mean that
I have to improve performance on the table that the icon is
associated with?

2. The icon labels have different captions - like 'Index Seek',
'Constant Scan' or 'Table Scan'. I guess that a 'Table Scan'
is potentially bad news, especially if the table that is being
scanned is very large, so this would tell me that I should
look at putting an index on the table. Are there other similar
interpretations I can make from the various other captions
to improve my performance?

TIA, 

--
Akin
aknak at aksoto dot idps dot co dot uk

Relevant Pages

  • Re: Interpreting the Estimated Execution Plan
    ... small table so SQL Server will return much faster the result performing ... > and will help your query. ... >> over the icon. ... >> aknak at aksoto dot idps dot co dot uk ...
    (microsoft.public.sqlserver.programming)
  • Re: Interpreting the Estimated Execution Plan
    ... If an item has a high cost, you can either create an index on a table or ... and will help your query. ... > over the icon. ... > aknak at aksoto dot idps dot co dot uk ...
    (microsoft.public.sqlserver.programming)
  • Re: Email MS Access File
    ... Although I used to have this mixed environment I never tried to email query ... The icon next to Print is View. ... T in Carolina ... I would select Excel and an email would open with the Query file ...
    (microsoft.public.access.externaldata)
  • Re: VISTA and OS X are not the same.
    ... That's because they are used to getting the Dot -- same OS, ... Especially since end-users care about end-user features, ... The jump from Mac OS6 to Mac OS7 makes the 0.1 OSX upgrades look like ... any icon spot already occupied, but he bug was that any icon that had been moved ...
    (comp.sys.mac.advocacy)
  • Default template (again.....)
    ... the document icon) and have all the headings etc. also use this font. ... Change the Word icon to an *.dot on the network also works for the ... first document only... ...
    (microsoft.public.word.docmanagement)