June 19, 2013

Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency

… caching of data at the filesystem level. The InnoDB indexes were built using ALTER TABLE fast index creation (merge sort). For the MyISAM… user=justin innodb_buffer_pool_size=64G innodb_log_file_size=4G innodb_file_per_table innodb_stats_on_metadata=off innodb_file_format=barracuda innodb_log…

Post: The small improvements of MySQL 5.6: Duplicate Index Detection

… new features that MySQL 5.6 brought: GTID-based replication, InnoDB Fulltext, Memcached integration, a more complete performance schema, online DDL…> ALTER TABLE test ADD INDEX (col2); Query OK, 0 rows affected (0.22 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> ALTER TABLE test…> ALTER TABLE test ADD INDEX (col2); Query OK, 0 rows affected (0.36 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> ALTER TABLE test…

Post: Migrating between MySQL schemas with Percona Xtrabackup

…-ddl.sql SELECT CONCAT(‘ALTER TABLE `’, table_name, ‘` DISCARD TABLESPACE;’) AS _ddl FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA=’orig’ AND ENGINE=’InnoDB‘; EOF mysql -N…-ddl.sql SELECT CONCAT(‘ALTER TABLE `’, table_name, ‘` IMPORT TABLESPACE;’) AS _ddl FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA=’orig’ AND ENGINE=’InnoDB‘; EOF For full…

Post: Percona XtraBackup 2.0.7 for MySQL available for download

… pool dump files). Percona XtraBackup has implemented support for the InnoDB Buffer Pool Preloading introduced in MySQL 5.6. Starting with… be imported by ALTER TABLE IMPORT TABLESPACE on MySQL and Percona Server 5.6 as described in Exporting and Importing Tables guide. Bugs… all InnoDB error or diagnostic messages are never printed by xtrabackup_56. Bug fixed #1169971. innobackupex would still run with FLUSH TABLES

Post: Percona XtraBackup 2.1.0 'release candidate' for MySQL available for download

… pool dump files). Percona XtraBackup has implemented support for the InnoDB Buffer Pool Preloading introduced in MySQL 5.6. Starting with… be imported by ALTER TABLE IMPORT TABLESPACE on MySQL and Percona Server 5.6 as described in Exporting and Importing Tables guide. Bugs… all InnoDB error or diagnostic messages are never printed by xtrabackup_56. Bug fixed #1169971. innobackupex would still run with FLUSH TABLES

Comment: Percona Server 5.5.30 with TokuDB for MySQL

… to convert 240 GB InnoDB table to TokuDB: “ERROR 1030 (HY000): Got error -1 from storage engine” The table has approximately 1.6 billion rows and I used “ALTER TABLE ENGINE=TokuDB” to do the conversion… to that, I was successful in converting a 10 GB table with a similar schema.

Post: Why ALTER TABLE shows as two transactions in SHOW ENGINE INNODB STATUS

When executing an ALTER TABLE, InnoDB (and XtraDB) will create two InnoDB transactions: One transaction is created when the table being ALTERed is locked by the server. This will show up as something like “TABLE… of MVCC. It’s not ACID). The largest part of ALTER TABLE not being completely crash safe in MySQL is the MySQL…

Post: Hacking to make ALTER TABLE online for certain changes

… remove auto_increment from 100G table. No matter if it’s InnoDB or MyISAM, you’d usually ALTER TABLE `huge_table` CHANGE `id` `id` int(6) NOT NULL and then wait hours for table rebuild… work for changing table comment as well, however – changing a comment with a help of ALTER TABLE does not rebuild the table, so we…

Post: ALTER TABLE: Creating Index by Sort and Buffer Pool Size

… and index size: mysql> show table status like “sbtest” \G *************************** 1. row *************************** Name: sbtest Engine: InnoDB Version: 10 Row_format: … If you’re having large tables and need to run ALTER TABLE which rebuilds the table or OPTIMIZE TABLE do not forget to enable …