| Bug #9868 | mysql_performance | ||
|---|---|---|---|
| Submitted: | 13 Apr 2005 12:46 | Modified: | 14 May 2005 14:53 |
| Reporter: | moemen mira | Email Updates: | |
| Status: | No Feedback | Impact on me: | |
| Category: | MySQL Server: Optimizer | Severity: | S1 (Critical) |
| Version: | mysql 5 | OS: | Linux (linux redhat 9) |
| Assigned to: | Assigned Account | CPU Architecture: | Any |
[13 Apr 2005 21:43]
Jorge del Conde
Hi! Your problem sounds like a performance/tuning question rather than a bug. I strongly suggest you purchase a MySQL Support license as I'm certain our support team will be able to guide you though the optimization/tuening process to speed up your query. You can order a support license by clicking on the following link: https://order.mysql.com/?ref=mjdc Thanks!
[14 May 2005 23:00]
Bugs System
No feedback was provided for this bug for over a month, so it is being suspended automatically. If you are able to provide the information that was originally requested, please do so and change the status of the bug back to "Open".
Description: I have a problem for running this query on my database "select distinct T1.item_id, T1.f2 from Persons as T1 , Emp as T2 , Emp as T3 where T1.item_type='6.' and T2.item_type='6.1.9.' and T3.item_type='6.1.' and T2.f2 like '1.1.16.%' and substring(T2.item_id,1,LOCATE('.',T2.item_id))=T1.item_id and substring(T3.item_id,1,LOCATE('.',T3.item_id))=T1.item_id and (T3.f2 ='4.1.1.') and (T3.f7 is null ) and (T2.f6 is null ) order by T1.f2 " the output time was so long, about 15.minuts even though i ran this query on previuos engine which was sql200 server and the output was not with so much time i don't know where is the problem in the performance of mysql , i copied the configuration of "my-huge.cnf" to be used as defualt configuration my sever is of 2GB RAM,2.4 pentium 4 processor the installation of mysql server was the defualt installation with no added configuration options Tables Type are of MYISAM Index of the query tables are of text type columns Tables records for the query case are 35,000 and 27,000 record for each table How to repeat: every time i ran the same query it takes much time please send fix reply (moemen@linux-plus.com) Suggested fix: I tried to change the key_buffer to big enough but with no enhancment Tried to disable the temp tables to be stored indisk but with no enhancment I don't know what is the problem is it bug or what