…logging queries which do not use indexes even if they take less time (–log-queries-not-using-indexes) Slow query log is great to spot really slow queries…slow query log As I already mentioned besides finding slowest queries it is important to find queries… WHERE id=XXX; SELECT id FROM forum WHERE…
Post: MySQL Slow query log in the table
May 31, 2007 By 1 Comment
…slow query log logged in mysql.slow_log…where being able to sort records by physical position quickly without need to have indexes would be quite handy I…log entirely in SQL finding most frequent slow query types or queries…
Post: Analyzing Slow Query Table in MySQL 5.6
February 18, 2013 By 1 Comment
…where your database response time is being spent. This month we saw the GA release of MySQL 5.6, and I…log.cc, MYSQL_QUERY_LOG::write(): 1945 /* For slow query log */ 1946 sprintf(query_time_buff, “%.6f”, ulonglong2double(query…Do you want to learn more about best practices for manipulating query logs…
Post: How to find MySQL queries worth optimizing ?
September 11, 2012 By 6 Comments
…query-digest report it is easy to find slow queries or queries which cause the large portion of the load on the system but how do…=1347397784; select * from sbtest where pad=’abc’; The query in this case has sent …this case if I index the table I get the following record in the slow query log: # Time:…
Post: MySQL Replication and Slow Queries
March 28, 2007 By 3 Comments
I just filed a bug regarding slow queries executed by replication thread are not being logged to the slow query log. This is not a big deal… which I think few people know about. It is especially bad if you’re using tools to analyze slow query log to find what queries take… if you do not, as I wrote in the bug report it is quite handy to have this information our where as query times…
Post: Find unused indexes
June 30, 2012 By Leave a Comment
… doing in the database. To accomplish our task of finding… statistics plugin gathering information. I usually enable it during…NAME from INNODB_INDEX_STATS WHERE CONCAT(INNODB_INDEX_STATS….slow query log. The concept is easy to understand. pt-index-usage reads the slow query log and execute every query…
Post: How to Identify Bad Queries in MySQL
January 10, 2011 By 16 Comments
…where I can’t be sure that I‘ve got a complete definition. Now, given the definition above, how do we find these queries…query-digest. Here’s how: It finds queries (or groups of queries) that are slow…
Post: How (not) to find unused indexes
October 16, 2009 By 2 Comments
… to be effective. I see this a lot in consulting issues where customers have queries that use a BETWEEN on …information (like QUAN) or set your slow query log to zero microseconds (5.1 feature) and then find someway to parse and EXPLAIN … old tool called mysqlidxchx which should be able to do this.
Post: Gathering queries from a server with Maatkit and tcpdump
July 1, 2009 By 23 Comments
…This lets us gather queries from servers that don’t have a slow query log enabled, at … 0.0110 9.8% 1 0.011017 I‘m kind of showing off the…do you suppose that one query was that took a tenth of a second? We can find out. mk-query… query took a tenth of a second to execute, and now you see where “SELECT…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…I find something, I compare it against the server’s variables or whatever other data I…queries the system runs, and hence the slow query log, is one of the more fruitful ways to analyze the system. What I usually do…
