… html after each run, so I find it convenient to set it up on crontab so that schema … name (in this case, parent_id) in the child and parent tables. Your environment may be like a lot … you can find a more comprehensive example here. Running SchemaSpy The syntax below if specific for MySQL, but …
Post: The small improvements of MySQL 5.6: Duplicate Index Detection
May 31, 2013 By Leave a Comment
…in-depth. If you try to do something like this in MySQL 5.5, you will succeed without errors or warnings: mysql…in set (0.00 sec) In previous versions of MySQL, you can create two indexes with the same columns (in… MySQL, for which we at Percona tend to find redundant indexes. And second, because in …
Post: How to fix your PRM cluster when upgrading to RHEL/CentOS 6.4
May 29, 2013 By 2 Comments
…Set: ms_MySQL [p_mysql] Masters: [ percona2 ] Slaves: [ percona3 ] Stopped: [ p_mysql:2 ] After the update and after fixing some small issues like…;) It’s still possible to find the command install crmsh (crm…Set: ms_MySQL [p_mysql] Masters: [ percona1 ] Slaves: [ percona2 percona3 ] So if you were in…
Post: MySQL Query Patterns, Optimized - Webinar questions followup
June 3, 2013 By 2 Comments
… table to store an interim result set, and then use that to ultimately …MySQL to scan the `title` table first, grouping by kind_id in index order. This made the first table in the EXPLAIN seem like… today is that sometimes you find unexpected differences in performance like this, so it pays …
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… In my previous blog post I compared MySQL 5.5.30 to MySQL 5.6.10, both with default settings…12GB of data in the largest table. You can find the individual SSB query definitions in my previous blog …, which is faster using MyISAM than InnoDB. Like the queries in Flight #3 that are faster using MyISAM…
Post: Multicast replication in Percona XtraDB Cluster (PXC) and Galera
June 5, 2013 By
…a lot of people setting up clusters with 3-6+ nodes on 1 Gbps networks. 1 Gbps seems like a lot, …17493 mysql 20u IPv4 39685 0t0 TCP *:3306 (LISTEN) Now, let’s re-do our above test: # 2 nodes in the …node_address setting on each node if this IP is not the default IP of the server. I could not find …
Post: Replication in MySQL 5.6: GTIDs benefits and limitations - Part 1
May 21, 2013 By 8 Comments
…the new features regarding replication in MySQL 5.6. They open …time? Downtime is something we like to avoid! Is it …find an answer to these questions, let’s create a simple replication configuration with one master and two slaves, all running MySQL… all servers have gtid_mode set to ON. Could it …
Post: Galera Flow Control in Percona XtraDB Cluster for MySQL
May 2, 2013 By 5 Comments
… feedback mechanism, unlike anything you find in standard async MySQL replication. It is my belief… tuning flow control in a master/slave cluster might be: mysql> set global wsrep_provider…make certification more expensive replication conflicts more likely and therefore time-consuming to the …
Post: MySQL 5.6 Compatible Percona Toolkit 2.2 Released
March 25, 2013 By 2 Comments
…_wait_timeout (introduced in MySQL 5.5) for metadata locks. Now –set-vars is used to set both of these…and tcpdump), so you shouldn’t have a problem finding queries to run and compare. pt-query-… 2.2 and pt-mysql-summary 2.2 have all the standard MySQL options built-in, like other tools: –user, –…
Post: Understanding the maximum number of columns in a MySQL table
April 8, 2013 By 5 Comments
…in MySQL, we’ll see that it’s defined as 4096. This, however, is not the true limit. To find…in MySQL, the defines can still found in the source. Basically, it’s why we can’t have nice things (like…
