…, but for the optimal production deployment you … EXCEPT a specified set of databases and tables…. intermediate server, thus resulting in less binary … see a large number of long-running queries in …query, but it’s always possible to build something more involved if that’s what you need. Q: What MySQL…
Post: MySQL 5.6 Compatible Percona Toolkit 2.2 Released
March 25, 2013 By 2 Comments
…query-digest 2.2 has fewer options now. Basically, we re-focused it on its primary objective: analyzing MySQL query…query-digest 2.2 can save results in JSON format (–output=json). This feature is still in development while we determine the optimal…
Post: MySQL Query Cache
July 27, 2006 By 70 Comments
…MySQL Performance optimization tasks but there are number of things you need to know. First let me clarify what MySQL Query…Query Cache – meaning cache where execution plans are cached. MySQL Query Cache is not. It does not cache the plan but full result sets…
Post: MySQL 5.5 and MySQL 5.6 default variable values differences
February 21, 2013 By 8 Comments
…MySQL 5.5 vs MySQL 5.6 performance results…set (0.00 sec) mysql [localhost] {msandbox} (test) > select * from var56 where variable_name=’OPTIMIZER_SWITCH’ \G *************************** 1. row *************************** VARIABLE_NAME: OPTIMIZER…
Post: How to find MySQL queries worth optimizing ?
September 11, 2012 By 6 Comments
…SET timestamp=1347398722; select * from sbtest a,sbtest b where a.id=5 and b.id=a.k; mysql…optimize this query in a simple way because scanning all that rows are actually needed to produce group by results…
Post: Working with large data sets in MySQL
July 5, 2007 By 12 Comments
What does working with large data sets in mySQL teach you ? Of course you have to learn a lot about query optimization, art of building summary tables and tricks of executing queries…… this however results in the challenge as results you’ve gotten for small data set may not apply to large data set so you need…
Post: MySQL: Followup on UNION for query optimization, Query profiling
August 14, 2006 By 14 Comments
…queries to see what exactly happens during query execution – very helpful for MySQL Performance optimization: mysql> flush status; Query OK, 0 rows affected (0.00 sec) mysql…
Post: Performance impact of complex queries
January 17, 2007 By 11 Comments
…MySQL Performance by complex queries on large data sets(ie some large aggregate queries) and batch jobs. It is not rare to see queries…would try to optimize throughput before latency, meaning if you have query which is doing … snapshot of current database with same results. In some cases you can’t …
Post: ORDER BY ... LIMIT Performance Optimization
September 1, 2006 By 100 Comments
…query log or by examining Hander statistics). If only 50 rows are examined to provide 10 rows of result set…MySQL still will not be able to use it as Optimizer is not smart enough yet to detect such cases: mysql…However if you’re dealing with LIMIT query with large offset efficiency will suffer. LIMIT…
Post: How fast can you sort data with MySQL ?
August 18, 2007 By 26 Comments
…MySQL can sort 1.000.000 rows, or rather return top 10 rows from sorted result set…optimal for given platform and given query (I did not test if it is the same for all platforms or data sets) – The optimal…
