MySQL

free howtos tutorials on mysql, Mysql 4.0, Mysql 5.0, Replication , Backup installation, configuration, support, technical quries, tips

Solved – Couldn’t execute ‘SELECT @@GTID_MODE’: Unknown system variable ‘GTID_MODE’ (1193)

i was getting the following error while taking database backup [root@solr7 ~]# mysqldump -u root -p**** ostn>ostn mysqldump: Couldn’t execute ‘SELECT @@GTID_MODE’: Unknown system variable ‘GTID_MODE’ (1193) This error is in part due to the introduction of Global Transaction Identifiers (GTIDs) in MySQL 5.6. GTIDs make it simple to # track and compare replication across(…)

How to Ignore Replication errors in MySQL

Some times you will be getting replication errors on the slaves , this might be coming because of the following any one of the reason Might have killed a query in between in the master server Duplicate entry Version difference , due to this some of the queries may not work in slaves Any other reasons You can put(…)

“Wrong permissions on configuration file, should not be world writable!”.

If you get this error message  like “Wrong permissions on configuration file, should not be world writable!” in phpMyAdmin and page can not load.It could be because config.inc.php is  given write permission. Simply run  chmod a-w config.inc.php command  it will solve your problem.

How recover corrupt table in MYSQL

Steps to Recover a corrupt table in mysql 1)      Go to  /var/lib/mysql/DB_Name  (Assuming DB is stored in given path) 2)      Run below command to scan whole DB to check for errors. myisamchk /var/lib/mysql/DB_NAME/*.MYI >> /tmp/myisamchk_log.txt (Report will be exported in .txt format) Use can see babel_user is corrupted 3)      Now run myisamchk –r babel_user.MYI command(…)

Example InnoDB my.cnf file for high end GNU/Linux machines

Example InnoDB my.cnf file for high end GNU/Linux machines #—————————————————————- # # my.cnf file # # # See: # # http://dev.mysql.com/doc/refman/5.1/en/server-options.html # http://dev.mysql.com/doc/refman/5.1/en/option-files.html # # You can also dump all the variables set for mysqld with: # # mysqld –verbose –help # #—————————————————————- [client] # These options apply to all client applications # Port and(…)

A my.cnf file designed for InnoDB heavy 8GB+ 64bit environments

This is an example config file for a 64bit 8GB GNU/Linux machine running mainly InnoDB. This config file will not work on a 32bit instance as it is configured to address more memory than 32bit procceses allow. This configuration assumes that this will be a replication master. If this is a slave and it doesn’t(…)

How to check the binlog position from Mysqldump

Bin log position is used to set the replication in MySQL.  One of the easiest way to set the replication in Mysql in the following ways. First Take the entire Dump of MySQL with mysql command mysqldump -u root -p –all-databases –master-data=2 > dump_file21102010 The second head the 100 lines in the dump file to(…)

MySQL Performance on Amazon EC2

Amazon EC2 makes it easy to get a large number of servers on which to run MySQL, but there are many choices to be made about the server and storage to use. There are 5 types of servers: small, large, extra-large, high-cpu medium and high-cpu extra-large. There are at least two types of storage: local disk and EBS.(…)

How to Optimize MySQL Performance with ZFS

This session focuses on ZFS performance with MySQL, and explores its suitability for deploying workloads based on MyISAM and InnoDB. ZFS performance relative to other file systems and the impact of ZFS compression on MySQL performance will also be examined. The ZFS Intent Log (ZIL) and the second level Adaptive Replacement Cache (L2ARC) benefit from low latencies, and benchmark results will be presented(…)