pt-osc执行日志
在对数据量为100000的表tb004做DROP COLUMN操作，pt-osc工具日志为：
Operation, tries, wait: analyze_table, 10, 1 copy_rows, 10, 0.25 create_triggers, 10, 1 drop_triggers, 10, 1 swap_tables, 10, 1 update_foreign_keys, 10, 1 Altering `db001`.`tb004`... Creating new table... Created new table db001._tb004_new OK. Altering new table... Altered `db001`.`_tb004_new` OK. 2019-07-10T18:15:03 Creating triggers... 2019-07-10T18:15:04 Created triggers OK. 2019-07-10T18:15:04 Copying approximately 89411 rows... 2019-07-10T18:15:06 Copied rows OK. 2019-07-10T18:15:06 Analyzing new table... 2019-07-10T18:15:07 Swapping tables... 2019-07-10T18:15:07 Swapped original and new tables OK. 2019-07-10T18:15:07 Dropping old table... 2019-07-10T18:15:07 Dropped old table `db001`.`_tb004_old` OK. 2019-07-10T18:15:07 Dropping triggers... 2019-07-10T18:15:07 Dropped triggers OK. Successfully altered `db001`.`tb004`.
pt-osc工具对MySQL执行的SQL命令为：
2019-07-10T18:15:04.271383+08:00 164 Query set autocommit=1 2019-07-10T18:15:04.272720+08:00 164 Query SHOW VARIABLES LIKE 'innodb\_lock_wait_timeout' 2019-07-10T18:15:04.276481+08:00 164 Query SET SESSION innodb_lock_wait_timeout=1 2019-07-10T18:15:04.277772+08:00 164 Query SHOW VARIABLES LIKE 'lock\_wait_timeout' 2019-07-10T18:15:04.280380+08:00 164 Query SET SESSION lock_wait_timeout=60 2019-07-10T18:15:04.281840+08:00 164 Query SHOW VARIABLES LIKE 'wait\_timeout' 2019-07-10T18:15:04.284424+08:00 164 Query SET SESSION wait_timeout=10000 2019-07-10T18:15:04.285704+08:00 164 Query SELECT @@SQL_MODE 2019-07-10T18:15:04.286965+08:00 164 Query SET @@SQL_QUOTE_SHOW_CREATE = 1/*!40101, @@SQL_MODE='NO_AUTO_VALUE_ON_ZERO,STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION'*/ 2019-07-10T18:15:04.288318+08:00 164 Query SELECT @@server_id /*!50038 , @@hostname*/ 2019-07-10T18:15:04.292463+08:00 165 Connect admin@172.28.37.35 on db001 using TCP/IP 2019-07-10T18:15:04.293623+08:00 165 Query set autocommit=1 2019-07-10T18:15:04.294971+08:00 165 Query SHOW VARIABLES LIKE 'innodb\_lock_wait_timeout' 2019-07-10T18:15:04.298053+08:00 165 Query SET SESSION innodb_lock_wait_timeout=1 2019-07-10T18:15:04.299318+08:00 165 Query SHOW VARIABLES LIKE 'lock\_wait_timeout' 2019-07-10T18:15:04.302018+08:00 165 Query SET SESSION lock_wait_timeout=60 2019-07-10T18:15:04.303291+08:00 165 Query SHOW VARIABLES LIKE 'wait\_timeout' 2019-07-10T18:15:04.305993+08:00 165 Query SET SESSION wait_timeout=10000 2019-07-10T18:15:04.307228+08:00 165 Query SELECT @@SQL_MODE 2019-07-10T18:15:04.308402+08:00 165 Query SET @@SQL_QUOTE_SHOW_CREATE = 1/*!40101, @@SQL_MODE='NO_AUTO_VALUE_ON_ZERO,STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION'*/ 2019-07-10T18:15:04.309580+08:00 165 Query SELECT @@server_id /*!50038 , @@hostname*/ 2019-07-10T18:15:04.310871+08:00 164 Query SHOW VARIABLES LIKE 'wsrep_on' 2019-07-10T18:15:04.313575+08:00 164 Query SHOW VARIABLES LIKE 'version%' 2019-07-10T18:15:04.316348+08:00 164 Query SHOW ENGINES 2019-07-10T18:15:04.317921+08:00 164 Query SHOW VARIABLES LIKE 'innodb_version' 2019-07-10T18:15:04.321005+08:00 164 Query SHOW VARIABLES LIKE 'innodb_stats_persistent' 2019-07-10T18:15:04.323618+08:00 164 Query SELECT @@SERVER_ID 2019-07-10T18:15:04.324841+08:00 164 Query SHOW GRANTS FOR CURRENT_USER() 2019-07-10T18:15:04.326061+08:00 164 Query SHOW FULL PROCESSLIST 2019-07-10T18:15:04.386880+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:04.389123+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:04.391521+08:00 164 Query SELECT CONCAT(@@hostname, @@port) 2019-07-10T18:15:04.394332+08:00 164 Query SHOW TABLES FROM `db001` LIKE 'tb004' 2019-07-10T18:15:04.395667+08:00 164 Query SHOW TRIGGERS FROM `db001` LIKE 'tb004' 2019-07-10T18:15:04.397242+08:00 164 Query /*!40101 SET @OLD_SQL_MODE := @@SQL_MODE, @@SQL_MODE := '', @OLD_QUOTE := @@SQL_QUOTE_SHOW_CREATE, @@SQL_QUOTE_SHOW_CREATE := 1 */ 2019-07-10T18:15:04.398378+08:00 164 Query USE `db001` 2019-07-10T18:15:04.399527+08:00 164 Query SHOW CREATE TABLE `db001`.`tb004` 2019-07-10T18:15:04.400863+08:00 164 Query /*!40101 SET @@SQL_MODE := @OLD_SQL_MODE, @@SQL_QUOTE_SHOW_CREATE := @OLD_QUOTE */ 2019-07-10T18:15:04.402364+08:00 164 Query EXPLAIN SELECT * FROM `db001`.`tb004` WHERE 1=1 2019-07-10T18:15:04.403883+08:00 164 Query SELECT table_schema, table_name FROM information_schema.key_column_usage WHERE referenced_table_schema='db001' AND referenced_table_name='tb004' 2019-07-10T18:15:04.411418+08:00 164 Query SHOW VARIABLES LIKE 'wsrep_on' 2019-07-10T18:15:04.414122+08:00 164 Query /*!40101 SET @OLD_SQL_MODE := @@SQL_MODE, @@SQL_MODE := '', @OLD_QUOTE := @@SQL_QUOTE_SHOW_CREATE, @@SQL_QUOTE_SHOW_CREATE := 1 */ 2019-07-10T18:15:04.415364+08:00 164 Query USE `db001` 2019-07-10T18:15:04.416546+08:00 164 Query SHOW CREATE TABLE `db001`.`tb004` 2019-07-10T18:15:04.417865+08:00 164 Query /*!40101 SET @@SQL_MODE := @OLD_SQL_MODE, @@SQL_QUOTE_SHOW_CREATE := @OLD_QUOTE */ 2019-07-10T18:15:04.419206+08:00 164 Query CREATE TABLE `db001`.`_tb004_new` ( `id` varchar(20) NOT NULL, `C1` int(11) DEFAULT NULL, `DT` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, `c6` int(11) DEFAULT NULL, `c5` int(11) DEFAULT NULL, `c4` int(11) DEFAULT NULL, `c7` int(11) DEFAULT NULL, `c8` int(11) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 2019-07-10T18:15:04.624271+08:00 164 Query ALTER TABLE `db001`.`_tb004_new` drop column c8 2019-07-10T18:15:04.934773+08:00 164 Query /*!40101 SET @OLD_SQL_MODE := @@SQL_MODE, @@SQL_MODE := '', @OLD_QUOTE := @@SQL_QUOTE_SHOW_CREATE, @@SQL_QUOTE_SHOW_CREATE := 1 */ 2019-07-10T18:15:04.936015+08:00 164 Query USE `db001` 2019-07-10T18:15:04.937303+08:00 164 Query SHOW CREATE TABLE `db001`.`_tb004_new` 2019-07-10T18:15:04.938540+08:00 164 Query /*!40101 SET @@SQL_MODE := @OLD_SQL_MODE, @@SQL_QUOTE_SHOW_CREATE := @OLD_QUOTE */ 2019-07-10T18:15:04.940366+08:00 164 Query CREATE TRIGGER `pt_osc_db001_tb004_del` AFTER DELETE ON `db001`.`tb004` FOR EACH ROW DELETE IGNORE FROM `db001`.`_tb004_new` WHERE `db001`.`_tb004_new`.`id` <=> OLD.`id` 2019-07-10T18:15:04.995376+08:00 164 Query CREATE TRIGGER `pt_osc_db001_tb004_upd` AFTER UPDATE ON `db001`.`tb004` FOR EACH ROW BEGIN DELETE IGNORE FROM `db001`.`_tb004_new` WHERE !(OLD.`id` <=> NEW.`id`) AND `db001`.`_tb004_new`.`id` <=> OLD.`id`;REPLACE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) VALUES (NEW.`id`, NEW.`c1`, NEW.`dt`, NEW.`c6`, NEW.`c5`, NEW.`c4`, NEW.`c7`);END 2019-07-10T18:15:05.055541+08:00 164 Query CREATE TRIGGER `pt_osc_db001_tb004_ins` AFTER INSERT ON `db001`.`tb004` FOR EACH ROW REPLACE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) VALUES (NEW.`id`, NEW.`c1`, NEW.`dt`, NEW.`c6`, NEW.`c5`, NEW.`c4`, NEW.`c7`) 2019-07-10T18:15:05.116027+08:00 164 Query EXPLAIN SELECT * FROM `db001`.`tb004` WHERE 1=1 2019-07-10T18:15:05.118327+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) ORDER BY `id` LIMIT 1 /*first lower boundary*/ 2019-07-10T18:15:05.119873+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX (`PRIMARY`) WHERE `id` IS NOT NULL ORDER BY `id` LIMIT 1 /*key_len*/ 2019-07-10T18:15:05.121305+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ * FROM `db001`.`tb004` FORCE INDEX (`PRIMARY`) WHERE `id` >= '1' /*key_len*/ 2019-07-10T18:15:05.122882+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '1')) ORDER BY `id` LIMIT 999, 2 /*next chunk boundary*/ 2019-07-10T18:15:05.124306+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '1')) ORDER BY `id` LIMIT 999, 2 /*next chunk boundary*/ 2019-07-10T18:15:05.126038+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '1')) AND ((`id` <= '100897')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:05.127575+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '1')) AND ((`id` <= '100897')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:05.211692+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:05.213153+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:05.215441+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '100898')) ORDER BY `id` LIMIT 5943, 2 /*next chunk boundary*/ 2019-07-10T18:15:05.216731+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '100898')) ORDER BY `id` LIMIT 5943, 2 /*next chunk boundary*/ 2019-07-10T18:15:05.220034+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '100898')) AND ((`id` <= '106246')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:05.221516+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '100898')) AND ((`id` <= '106246')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:05.602099+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:05.603631+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:05.605879+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '106247')) ORDER BY `id` LIMIT 7542, 2 /*next chunk boundary*/ 2019-07-10T18:15:05.607175+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '106247')) ORDER BY `id` LIMIT 7542, 2 /*next chunk boundary*/ 2019-07-10T18:15:05.610992+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '106247')) AND ((`id` <= '12331')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:05.612558+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '106247')) AND ((`id` <= '12331')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.292364+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:06.293864+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:06.296249+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '12332')) ORDER BY `id` LIMIT 6202, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.297653+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '12332')) ORDER BY `id` LIMIT 6202, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.301010+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '12332')) AND ((`id` <= '15422')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.311117+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '12332')) AND ((`id` <= '15422')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.448604+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:06.450120+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:06.452431+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '15423')) ORDER BY `id` LIMIT 8709, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.453744+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '15423')) ORDER BY `id` LIMIT 8709, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.457900+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '15423')) AND ((`id` <= '23261')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.459481+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '15423')) AND ((`id` <= '23261')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.622244+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:06.623716+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:06.626148+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '23262')) ORDER BY `id` LIMIT 12224, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.627482+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '23262')) ORDER BY `id` LIMIT 12224, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.632599+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '23262')) AND ((`id` <= '38324')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.634037+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '23262')) AND ((`id` <= '38324')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.850117+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:06.851574+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:06.854054+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '38325')) ORDER BY `id` LIMIT 16344, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.855361+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '38325')) ORDER BY `id` LIMIT 16344, 2 /*next chunk boundary*/ 2019-07-10T18:15:06.861804+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '38325')) AND ((`id` <= '53034')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:06.863334+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '38325')) AND ((`id` <= '53034')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:07.143641+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:07.145231+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:07.147665+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '53035')) ORDER BY `id` LIMIT 20280, 2 /*next chunk boundary*/ 2019-07-10T18:15:07.148966+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '53035')) ORDER BY `id` LIMIT 20280, 2 /*next chunk boundary*/ 2019-07-10T18:15:07.156635+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '53035')) AND ((`id` <= '80422')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:07.158179+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '53035')) AND ((`id` <= '80422')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:07.546098+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:07.547632+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:07.550054+08:00 164 Query EXPLAIN SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '80423')) ORDER BY `id` LIMIT 22400, 2 /*next chunk boundary*/ 2019-07-10T18:15:07.551354+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '80423')) ORDER BY `id` LIMIT 22400, 2 /*next chunk boundary*/ 2019-07-10T18:15:07.559527+08:00 164 Query SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) ORDER BY `id` DESC LIMIT 1 /*last upper boundary*/ 2019-07-10T18:15:07.560937+08:00 164 Query EXPLAIN SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '80423')) AND ((`id` <= '99999')) LOCK IN SHARE MODE /*explain pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:07.562464+08:00 164 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '80423')) AND ((`id` <= '99999')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/ 2019-07-10T18:15:07.893310+08:00 164 Query SHOW WARNINGS 2019-07-10T18:15:07.894806+08:00 164 Query SHOW GLOBAL STATUS LIKE 'Threads_running' 2019-07-10T18:15:07.897361+08:00 164 Query ANALYZE TABLE `db001`.`_tb004_new` /* pt-online-schema-change */ 2019-07-10T18:15:07.965519+08:00 164 Query RENAME TABLE `db001`.`tb004` TO `db001`.`_tb004_old`, `db001`.`_tb004_new` TO `db001`.`tb004` 2019-07-10T18:15:08.223514+08:00 164 Query DROP TABLE IF EXISTS `db001`.`_tb004_old` 2019-07-10T18:15:08.362410+08:00 164 Query DROP TRIGGER IF EXISTS `db001`.`pt_osc_db001_tb004_del` 2019-07-10T18:15:08.392249+08:00 164 Query DROP TRIGGER IF EXISTS `db001`.`pt_osc_db001_tb004_upd` 2019-07-10T18:15:08.422315+08:00 164 Query DROP TRIGGER IF EXISTS `db001`.`pt_osc_db001_tb004_ins` 2019-07-10T18:15:08.445194+08:00 164 Query SHOW TABLES FROM `db001` LIKE '\_tb004\_new' 2019-07-10T18:15:08.447215+08:00 165 Quit 2019-07-10T18:15:08.447328+08:00 164 Quit
常规检查和设置
## 检查执行线程数量 SHOW GLOBAL STATUS LIKE 'Threads_running' ## 获取从库信息 SHOW FULL PROCESSLIST ## 检查是是PXC群集 SHOW VARIABLES LIKE 'wsrep_on' ## 检查表是否有触发器 SHOW TRIGGERS FROM `db001` LIKE 'tb004' ## 检查表是否有外键 SELECT table_schema, table_name FROM information_schema.key_column_usage WHERE referenced_table_schema='db001' AND referenced_table_name='tb004' ## 设置会话超时和锁超时 SET SESSION wait_timeout=10000 SET SESSION lock_wait_timeout=60 ## 查看原表创建语句 SHOW CREATE TABLE `db001`.`tb004`
创建触发器
## 删除操作触发器 CREATE TRIGGER `pt_osc_db001_tb004_del` AFTER DELETE ON `db001`.`tb004` FOR EACH ROW DELETE IGNORE FROM `db001`.`_tb004_new` WHERE `db001`.`_tb004_new`.`id` <=> OLD.`id`; ## 更新操作触发器 CREATE TRIGGER `pt_osc_db001_tb004_upd` AFTER UPDATE ON `db001`.`tb004` FOR EACH ROW BEGIN DELETE IGNORE FROM `db001`.`_tb004_new` WHERE !(OLD.`id` <=> NEW.`id`) AND `db001`.`_tb004_new`.`id` <=> OLD.`id`; REPLACE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) VALUES (NEW.`id`, NEW.`c1`, NEW.`dt`, NEW.`c6`, NEW.`c5`, NEW.`c4`, NEW.`c7`); END ## 插入操作触发器 CREATE TRIGGER `pt_osc_db001_tb004_ins` AFTER INSERT ON `db001`.`tb004` FOR EACH ROW REPLACE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) VALUES (NEW.`id`, NEW.`c1`, NEW.`dt`, NEW.`c6`, NEW.`c5`, NEW.`c4`, NEW.`c7`)
第一次数据拷贝
在第一次数据拷贝前，先执行下面EXPLAIN语句获取表数据量：
EXPLAIN SELECT * FROM `db001`.`tb004` WHERE 1=1
如果表数据量较少，则选择通过一次全表扫描将所有数据复制到新表：
2019-07-10T17:34:46.226165+08:00 154 Query EXPLAIN SELECT * FROM `db001`.`tb002` WHERE 1=1 2019-07-10T17:34:46.339284+08:00 154 Query EXPLAIN SELECT `c1`, `c2`, `c3` FROM `db001`.`tb002` LOCK IN SHARE MODE /*explain pt-online-schema-change 19569 copy table*/ 2019-07-10T17:34:46.340637+08:00 154 Query INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb002_new` (`c1`, `c2`, `c3`) SELECT `c1`, `c2`, `c3` FROM `db001`.`tb002` LOCK IN SHARE MODE /*pt-online-schema-change 19569 copy table*/
如果表数据量超过一定阈值，则选择通过N次范围扫描将数据复制到新表。
当chunk-size和chunk-time两者都未指定时，chunk-size默认值为1000，chunk-time默认值为0.5S，第一次按照chunk-size来进行数据复制，然后根据第一次复制的时间动态调整chumk-size的大小，以适应服务器的性能变化，如上一次复制1000行消耗0.1S，则下次动态调整chumk-size为5000。
1、获取第一次范围扫描的最小值和行长度：
SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) ORDER BY `id` LIMIT 1 /*first lower boundary*/ SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX (`PRIMARY`) WHERE `id` IS NOT NULL ORDER BY `id` LIMIT 1 /*key_len*/
2、获取第一次范围扫描的最大值和第二次范围扫描的最小值：
SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '1')) ORDER BY `id` LIMIT 999, 2
3、复制数据至新表：
INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '1')) AND ((`id` <= '100897')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/
4、根据步骤3的操作时长调整下次操作的chumk-size，由于第一次复制1000条数据耗时较短，第二次复制数据的chumk-size被更新为5943。
5、获取第二次范围扫描的最大值和第三次范围扫描的最小值：
SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '100898')) ORDER BY `id` LIMIT 5943, 2
6、循环第二次至第N次数数据复制。
最后一次数据拷贝
1、通过本次的范围扫描的最小值和chumk-size获取本次范围扫描的最大值：
SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '80423')) ORDER BY `id` LIMIT 22400, 2 /*next chunk boundary*/
2、步骤1未返回期望的2行记录，判断复制操作执行到数据尾部，获取当前表上最大值：
SELECT /*!40001 SQL_NO_CACHE */ `id` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) ORDER BY `id` DESC LIMIT 1 /*last upper boundary*/
3、根据本次的范围扫描的最小值和当前表上最大值，做最后一次数据复制：
INSERT LOW_PRIORITY IGNORE INTO `db001`.`_tb004_new` (`id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7`) SELECT `id`, `c1`, `dt`, `c6`, `c5`, `c4`, `c7` FROM `db001`.`tb004` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= '80423')) AND ((`id` <= '99999')) LOCK IN SHARE MODE /*pt-online-schema-change 23795 copy nibble*/
4、所有数据复制完成，更新新表统计信息
ANALYZE TABLE `db001`.`_tb004_new` /* pt-online-schema-change */
5、更换原表和新表的表名：
RENAME TABLE `db001`.`tb004` TO `db001`.`_tb004_old`, `db001`.`_tb004_new` TO `db001`.`tb004`
6、清理原表和触发器：
DROP TABLE IF EXISTS `db001`.`_tb004_old` DROP TRIGGER IF EXISTS `db001`.`pt_osc_db001_tb004_del` DROP TRIGGER IF EXISTS `db001`.`pt_osc_db001_tb004_upd` DROP TRIGGER IF EXISTS `db001`.`pt_osc_db001_tb004_ins`
7、确认新表已正确改名：
SHOW TABLES FROM `db001` LIKE '\_tb004\_new'
8、pt-osc工具执行完成。