A Microsoft Office (Excel, Word) forum. OfficeFrustration

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » OfficeFrustration forum » Microsoft Access » Database Design
Site Map Home Register Authors List Search Today's Posts Mark Forums Read  

Can floating point numeric index use inequality in queries?



 
 
Thread Tools Display Modes
  #1  
Old July 15th, 2008, 05:45 PM posted to microsoft.public.access.tablesdbdesign
harolde
external usenet poster
 
Posts: 1
Default Can floating point numeric index use inequality in queries?

I have 2 floating point numeric columns that I am using in queries with
inequality criteria for those columns.

Will indexes on those column be useful (i.e. can they be used to speed up
the query)?
  #2  
Old July 15th, 2008, 11:44 PM posted to microsoft.public.access.tablesdbdesign
John W. Vinson/MVP
external usenet poster
 
Posts: 325
Default Can floating point numeric index use inequality in queries?


"harolde" wrote in message
...
I have 2 floating point numeric columns that I am using in queries with
inequality criteria for those columns.

Will indexes on those column be useful (i.e. can they be used to speed up
the query)?


Yes. Depending on how the numbers are generated, though, you may have
roundoff error causing mismatches - two values which look identical might be
off in the last decimal place.


  #3  
Old July 16th, 2008, 06:25 PM posted to microsoft.public.access.tablesdbdesign
Jerry Whittle
external usenet poster
 
Posts: 4,732
Default Can floating point numeric index use inequality in queries?

A criteria of = might be a problem; however or criteria might really
speed things up. A lot depends on the cardinality of your data.

In cases like this, a good old-fashion stopwatch ends a lot of speculation.
Just remember to do the timing after running the query at least once so that
Access can optimize it.
--
Jerry Whittle, Microsoft Access MVP
Light. Strong. Cheap. Pick two. Keith Bontrager - Bicycle Builder.

"harolde" wrote:

I have 2 floating point numeric columns that I am using in queries with
inequality criteria for those columns.

Will indexes on those column be useful (i.e. can they be used to speed up
the query)?

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 10:58 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 OfficeFrustration.
The comments are property of their posters.