…We had lots of questions. I did not have time to answer some and others are better answered in writing…will “WHERE a IN (2-4)” be worse then “WHERE a IN (2,3,4)”? Another word is range for IN clause… how MySQL will execute the join. If it will…indicates a double linked list. Innodb has double linked …
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…of CPU time. PZ: We will see how it plays when we can see more benchmarks…. they were not matched by query where clause when it was not resolved by … O_DIRECT works well to remove double buffering. In distant future, I …to write not-modified pages if this will get sequential write. Say if we have 1MB…
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
…it is too late to write about stuff happened at Users Conference but… per CPU just keeps doubling. It is also rather interesting how is sort file … rows if they do not match where clause (think for example about running not-… patches he has provided will be merged soon if not we should test them …
Post: MySQL: Followup on UNION for query optimization, Query profiling
August 14, 2006 By 14 Comments
…mention double …IN clauses. … | | Handler_update | 0 | | Handler_write | 14 | +—————————-+——-+ …see how …now will …where; Using filesort | +—-+————-+——–+——-+—————+——+———+——+——-+—————————–+ 1 row in set (0.00 sec) We…
Comment: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
…because the user probably knows how much memory can be … records in those cases where the query could have …non-standard “FOR UPDATE†clause does cause a select…With checksums, the InnoDB double page write might be a good thing…is important, but we expect that real applications will tend to keep …
