… just for this project. Query Validation It is often hard to ensure queries work same way with different MySQL version, unless you have very detailed automated QA. So what you can do is get the backup of the database and get query…
Post: MySQL Upgrade Webinar Questions Followup
June 28, 2012 By 7 Comments
… to be depreciated in future MySQL versions also MyISAM tables are essentially at the state they were in MySQL 4.1 while Innodb… – this is not needed as MySQL 5.5 continues to support various character sets same as previous MySQL versions. Moreover utf8 character set… queries just need to be changed or supplemented with hints to get to old execution plans. In many cases though you can get…
Post: Should we give a MySQL Query Cache a second chance ?
April 10, 2011 By 64 Comments
… version matches for all tables on which query depends on. If not you need to re-generate the query result. Removing of stale queries… than wire speed for 1Gb networks. Plus if we can get MySQL protocol to support such light compression in addition to zlib…. Improve Manageability What is in the MySQL Query Cache ? How many hits did we get for this query item ? Right now none of such…
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
…MySQL server or causing all the connections to get depleted. There are some other interesting consequences as well for application that use MySQL versions…
Post: MySQL Indexing Best Practices: Webinar Questions Followup
August 16, 2012 By 4 Comments
… directions for different queries. This will use fast primary key for some queries and use key …` IN (5)” regarding indexes and performance? A: Recent MySQL versions are smart enough to convert id IN (5…works because by scanning data in index order MySQL gets data in already sorted order and looks at…
Post: Is MySQL 5.6 slower than MySQL 5.5?
February 18, 2013 By 23 Comments
…have to be considered for the query the more time the query optimization is likely to take. …our Percona Server for MySQL version 5.6 release. Another thing to remember about MySQL 5.6 is – …this slowness comes from Performance Schema ? Whenever we get difference higher or lower with high concurrency …
Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark
March 11, 2013 By 7 Comments
… I modified the queries to use ANSI JOIN syntax. No other changes to the queries were made. Test Environment The MySQL versions used at… versions, and as you can see above, MySQL 5.6 outperformed MySQL 5.5.30 with the big buffer pool. Why is the MySQL…_RATE: 0.032257023966968806 * PAGES_WRITTEN_RATE: 0 NUMBER_PAGES_GET: 6731790 * NUMBER_PAGES_GET: 6731253 HIT_RATE: 995 * HIT_RATE: 0 YOUNG…
Post: Slow Query Log analyzes tools
September 6, 2006 By 84 Comments
… long_query_time=0 This patch is adapted version of patch by Georg Richter which was made to run with recent MySQL version. Now why do not we use general log instead ? Unfortunately general logs queries before queries are executed (and… you query log and get back to unpatched version. It is best if you generate this log for all your queries with long_query_time…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…mysql> use ontime1; Database changed mysql> show table status like ‘ontime_fact’G *************************** 1. row *************************** Name: ontime_fact Engine: InnoDB Version…
Post: The story of one MySQL Upgrade
October 8, 2010 By 8 Comments
I recently worked on upgrading MySQL from one of very early MySQL 5.0 versions to Percona Server 5.1. This was a… the same position again and used tcpdump and mk-query-digest to get sample read traffic from both master and slave. –sample… with New MySQL version upgrade involves new Operating System and hardware and any of them could be potential cause of rollback. MySQL Upgrade…
