| List: | General Discussion | « Previous MessageNext Message » | |
| From: | Rob Wultsch | Date: | April 11 2008 3:53pm |
| Subject: | Re: MySQl 5.0 optimization problem | ||
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On Fri, Apr 11, 2008 at 6:47 AM, Ben Clewett <ben@stripped> wrote: > A COUNT() forces the system to read every row in order to count them... That is not strictly the case. A count(field) can use an index scan rather than a sequential scan, which may or may not be faster. Also some count(field) can queries be optimized away if a field is NOT NULL and the type is myisam. Posting a >Show status; might be useful. DDL is always helpful... -- Rob Wultsch wultsch@stripped wultsch (aim)
| Thread | ||
|---|---|---|
| • MySQl 5.0 optimization problem | Victor Danilchenko | 11 Apr |
| • Re: MySQl 5.0 optimization problem | Ben Clewett | 11 Apr |
| • Re: MySQl 5.0 optimization problem | Wm Mussatto | 11 Apr |
| • Re: MySQl 5.0 optimization problem | Ben Clewett | 11 Apr |
| • Re: MySQl 5.0 optimization problem | Victor Danilchenko | 11 Apr |
| • Re: MySQl 5.0 optimization problem | Rob Wultsch | 11 Apr |
