Timo

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	30 reputation	bio	website		visits	member for	7 months
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Apr 14	awarded	Notable Question
Feb 11	awarded	Popular Question
Dec 11	comment	Slow query with straight_join for small result But in my case I do a lot of bulk inserts to import new data (every 10 minutes). And the result of my performance-tests was that mysql slows down very hard without this OPTIMIZE-frequence.
Dec 9	awarded	Commentator
Dec 9	comment	Slow query with straight_join for small result My “problem” is that I don’t know the “better” plan than the optimizer. Especially I don’t understand why the “fast” straight_join-query is so slowly for querys (profiles) with less (or no) data in the mentioncache-table (just testet: for a small profile the normal-join query is about 300 times faster!). Do you have any idea for this huge difference?
Dec 9	comment	Slow query with straight_join for small result Hi Michal, thanks for your reply. I added the explain for the „normal“ join query. You are right: In this case MySQL uses a different query plan: In the straight_join-case the mention-table is the first table and the mentioncache-table is the last table. In the normal join-case the mentioncache table is the first (!) table an the mention-table the second one.
Dec 9	comment	Slow query with straight_join for small result Hi Rick, thanks for your reply. I do a optimize table per cron every 2-4 hours, so I think the statistics of the table should be up-to-date.
Dec 9	revised	Slow query with straight_join for small result added 968 characters in body
Dec 4	asked	Slow query with straight_join for small result
Nov 8	awarded	Tumbleweed
Nov 1	asked	Slow INSERT INTO SELECT statement – not repeatable!
Oct 19	asked	MySQL: Execute CREATE TEMPORARY TABLE SELECT just one time?
Oct 18	comment	Slow insert with MySQL full-text index Sorry - don't seen your comment. The table has about 30 varchar and text fields, some indexes on varchar-fields and a fulltext index over the three fields title_text (char(255)), content_text (text), author_text (char(255)). In the table are about 210.000 data sets, the table size is about 2,5 GB and the index-size about 0,5 GB. The insert queries are done for every new data set (no combined query for all inserts). Do you need more informations?
Oct 17	revised	Slow complex query with group/order Remove some errors in query
Oct 17	suggested	suggested edit on Slow complex query with group/order
Oct 17	comment	Slow complex query with group/order I don't know why but the query is even slow just with one more join table. I tested it with the attachment-table and the visiteditems-table - in both cases the query performs really slow. It seems that the structure of the joins with the subquery is very slowly. With a "normal" join without the subquery the performance is much better.
Oct 17	asked	Slow insert with MySQL full-text index
Oct 16	comment	Slow complex query with group/order Thanks for your tips! Unfortunately even a simpler version of your query (without the case when construct and the join on the mentionfeedscores-table) returns a result after 400 (!) seconds. Do you have any idea why the performance is so bad?
Oct 16	comment	Slow complex query with group/order Seems that index-changing in the mentionfeedscores-table does not change the performance of this query.
Oct 16	comment	Slow complex query with group/order The tables has the following indexes: PRIMARY id, INDEX mention_id, INDEX feed_id. The condition is in the on-part because i thought its better to join less data.