MS SQL Development
 
Forums: » Register « |  User CP |  Games |  Calendar |  Members |  FAQs |  Sitemap |  Support | 
User Name:
Password:
Remember me

The Shed is going Social! Join us on FaceBook and Twitter and chime in on the conversation.

Go Back   Dev Shed ForumsDatabasesMS SQL Development

Reply
Add This Thread To:
  Del.icio.us   Digg   Google   Spurl   Blink   Furl   Simpy   Y! MyWeb 
Thread Tools Search this Thread Rate Thread Display Modes
 
Unread Dev Shed Forums Sponsor:
  #1  
Old October 15th, 2003, 02:05 PM
ricesteam ricesteam is offline
Junior Member
Dev Shed Newbie (0 - 499 posts)
 
Join Date: Oct 2003
Posts: 2 ricesteam User rank is Just a Lowly Private (1 - 20 Reputation Level) 
Time spent in forums: < 1 sec
Reputation Power: 0
how to increase performance?

Hi, I am using this MS SQL statement:

"SELECT * FROM dbo.Products INNER JOIN dbo.InvPrice ON dbo.Products.ProductCode = dbo.InvPrice.ProductCode WHERE (dbo.Products.ProductCode LIKE '%" +Prod__Search2+ "%' AND Supplier LIKE '" + Prod__Select2+ "' OR Description LIKE '%" + Prod__Search2+ "%' AND Supplier LIKE '" + Prod__Select2+ "') AND (dbo.InvPrice.PriceCode = 'AA')"

For an asp search page, but the results takes a long time to display. If I take out the wildcard '%' eg. i change (...LIKE '%" +Prod__Search2+ "%'...) to (...LIKE '" + Prod__Search2+ "'...) for an exact phrase search, the results show up instantaneous, but I don't want an exact phrase search.

My database consists of 250,000 records. Any solutions?

Thanks.

Reply With Quote
  #2  
Old October 15th, 2003, 03:06 PM
Scorpions4ever's Avatar
Scorpions4ever Scorpions4ever is offline
Banned ;)
Dev Shed God 9th Plane (9000 - 9499 posts)
 
Join Date: Nov 2001
Location: Woodland Hills, Los Angeles County, California, USA
Posts: 9,387 Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level)Scorpions4ever User rank is General 46th Grade (Above 100000 Reputation Level) 
Time spent in forums: 1 Month 4 Weeks 1 Day 21 h 39 m 3 sec
Reputation Power: 4080
The moment you do something like this:
LIKE '%" +Prod__Search2+ "%'

then SQL has no choice, but to do a full table scan, because you have wildcards on both sides of the expression. If you did something like this instead:
LIKE Prod__Search2+ "%'
then the SQL engine could potentially use an index, since the wildcard is only on the right. However, since you have wild cards on both sides of the words to be searched, there's no way to prevent a table scan.

The only solution that occurs to me is if you can break up the phrase into individual words and then xref back to the phrase table. Then u can search for the words with = instead of LIKE and make the joins much faster.
__________________
Up the Irons
What Would Jimi Do? Smash amps. Burn guitar. Take the groupies home.
"Death Before Dishonour, my Friends!!" - Bruce D ickinson, Iron Maiden Aug 20, 2005 @ OzzFest
Down with Sharon Osbourne

Reply With Quote
  #3  
Old October 15th, 2003, 03:18 PM
ricesteam ricesteam is offline
Junior Member
Dev Shed Newbie (0 - 499 posts)
 
Join Date: Oct 2003
Posts: 2 ricesteam User rank is Just a Lowly Private (1 - 20 Reputation Level) 
Time spent in forums: < 1 sec
Reputation Power: 0
What if the search is not for a phrase but for a code? eg. PC-AK04
PC09232, PC-add32, etc... and when the user types in PC, all those queries containing PC in front would come up.

I have tried useing '%' on one side only, but the performance is still slow.

thanks.

Reply With Quote
Reply

Viewing: Dev Shed ForumsDatabasesMS SQL Development > how to increase performance?

Developer Shed Advertisers and Affiliates



Thread Tools  Search this Thread 
Search this Thread:

Advanced Search
Display Modes  Rate This Thread 
Rate This Thread:


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 On
HTML code is Off
View Your Warnings | New Posts | Latest News | Latest Threads | Shoutbox
Forum Jump

Forums: » Register « |  User CP |  Games |  Calendar |  Members |  FAQs |  Sitemap |  Support | 
  
 


Powered by: vBulletin Version 3.0.5
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd.

© 2003-2013 by Developer Shed. All rights reserved. DS Cluster - Follow our Sitemap