… at the MySQL Performance Blog, we’ve been discussing the several new features that MySQL 5.6 brought: GTID-based replication, InnoDB Fulltext… creation of the duplicate index. Does it mean that tools like pt-duplicate-key-checker will not be necessary for MySQL 5.6? Let… includes mysqlindexcheck, similar to pt-duplicate-key-checker, but it does not detect all cases. For example: mysql> alter table test add index…
Post: Is your MySQL buffer pool warm? Make it sweat!
April 16, 2013 By 6 Comments
… mind! There are numerous solutions for MySQL high availability. Many rely on MySQL’s asynchronous replication to maintain a warm standby server which… statements that match no rows or insert statements that have duplicate key errors may be faster than an actual database write. The…
Post: Repair MySQL 5.6 GTID replication by injecting empty transactions
March 26, 2013 By 1 Comment
In a previous post I explained how to repair MySQL 5.6 GTID replication using two different methods. I didn’t mention… that the replication in slave server is not working because of an error: Last_SQL_Error: Error ‘Duplicate entry ’4′ for key ‘PRIMARY… is found in Percona Toolkit for MySQL. Last week I gave a talk at Percona MySQL University @Toronto about GTID. It includes…
Post: How Does Semisynchronous MySQL Replication Work?
January 19, 2012 By 24 Comments
… asked about MySQL‘s semi-synchronous replication. I find that there are often a number of misconceptions about how semi-synchronous replication really… no guarantee they can apply and commit it successfully themselves (duplicate key error, anyone?). If any of these problems happens, it’s…
Post: The story of one MySQL Upgrade
October 8, 2010 By 8 Comments
… number of other environments. INSERT ON DUPLICATE KEY UPDATE had a unfair share of replication issues in MySQL 5.0. There are number of… functionality is used. Happily there are only few INSERT ON DUPLICATE KEY UPDATE query instances, and only one of them into table… application not to use INSERT ON DUPLICATE KEY UPDATE in this instance so it was done. So replication was running properly but does…
Post: Percona XtraDB Cluster (PXC): what about GRA_*.log files ?
December 19, 2012 By Leave a Comment
…-header /tmp/GRA-header: MySQL replication log Now we need to select one GRA log file: [root@node2 mysql]# ls GRA_*.log GRA…: data [root@node2 mysql]# file GRA_3_3-bin.log GRA_3_3-bin.log: MySQL replication log [root@node2 mysql]# mysqlbinlog -vvv GRA… on table sakila.actor; Duplicate entry ’447′ for key ‘PRIMARY’, Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event’s…
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
… born same as bunch of others due to statement level MySQL Replication which among other requirements, needs all auto-increment values in… probably similar problems in INSERT IGNORE and ON DUPLICATE KEY UPDATE cases. Now In MySQL 5.1+ it is also possible to fix… have the problems because they target at least MySQL 5.1 with row level replication readily available. Speaking about community items the…
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
… reads consistent and therefore makes the replication between servers consistent. If you execute SELECT *…the gap locks except for foreign-key constraint checking or duplicate-key checking. The most important difference…en/innodb-locks-set.html. Conclusion MySQL uses REPEATABLE READ as the default…
Post: Announcing Percona Server 5.1.65-14.0
September 4, 2012 By Leave a Comment
… upstream MySQL bug #66301. Concurrent INSERT … ON DUPLICATE KEY UPDATE statements on a table with an AUTO_INCREMENT column could result in spurious duplicate key…. Bug fixed #890623 (Alexey Kopytov). A server acting as a replication slave with the query cache enabled could crash with glibc…
Post: How to create/restore a slave using GTID replication in MySQL 5.6
February 8, 2013 By 7 Comments
… are many documents about that: http://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html One thing that worths… restore it on the slave to set up a new replication server. master > show global variables like ‘gtid_executed’; +—————+——————————————-+ | Variable_name…, if you don’t get any error like primary/unique key duplication then you can run the pt-table-checksum and pt…
