… EXPLAIN statement in MySQL 4.1 is EXTENDED keyword which provides you with some helpful additional information on query optimization. It should be… as what other notes optimizer may wish to tell us. It is best seen by example: mysql> explain extended select * from sbtest where… about last query – even if it looks like there is a whole big deal of optimization being done query is executed extremely poor, completing…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…been several MySQL bugs opened about multi-core scalability (concurrent queries, autoincrement, concurrent… (150GB) that is showing poor performance for full table scans…without having to run the OPTIMIZE? HT: Since OPTIMIZE rebuilds the whole … “show innodb statusâ€. select * from table where id=5…
Comment: How to find wrong indexing with glance view
March 8, 2010 By 27 Comments
… MySQL optimizer sometimes appears to become rather overwhelmed by the number of indexes and tables to choose from for moderately complex queries and selects… cardinality with roughly even distributions. Nearly always a poor choice to use for any query. This is why most if not all…
Post: Watch out for Marketing benchmarks
August 23, 2006 By 7 Comments
…MySQL 4.1 vs 5.0 benchmarks which were done only benchmarks which show MySQL 5.0 is faster were selected…optimizer features. I can help in many cases to work around MySQL limitations or design application so it uses MySQL…MySQL I recommended not to use MySQL for certain applications (ie when queries…
