# column comments in chinese character changed to messy code after using pt-osc **URL:** https://forums.percona.com/t/column-comments-in-chinese-character-changed-to-messy-code-after-using-pt-osc/5929 **Category:** Percona Toolkit **Created:** [October 12, 2017, 4:32am UTC](https://forums.percona.com/t/column-comments-in-chinese-character-changed-to-messy-code-after-using-pt-osc/5929 "2017-10-12T04:32:37Z") **Posts on this page:** 1 **Page:** 1
### Author: ![romber](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/romber/32/36_2.png) [@romber](https://forums.percona.com/u/romber) #### Post date: [October 12, 2017, 4:32am UTC](https://forums.percona.com/t/column-comments-in-chinese-character-changed-to-messy-code-after-using-pt-osc/5929/1 "2017-10-12T04:32:37Z")
environment: rhel6 + mysql5.6 + pt-osc 3.0.3 how to repeat: mysql\> show create table test02; ±-------±-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | ±-------±-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | test02 | CREATE TABLE “test02” ( “id” int(11) NOT NULL DEFAULT ‘0’, [COLOR=#FF0000] “name” varchar(10) DEFAULT NULL COMMENT ‘姓名’, “col1” int(10) DEFAULT NULL COMMENT ‘字段1’, PRIMARY KEY (“id”) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 | ±-------±-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec) mysql\> exit Bye You have new mail in /var/spool/mail/root [root@rhel01 ~]# pt-online-schema-change --host=localhost --port=3306 --user=root --password=xxx --progress time,30 --print --alter=“modify column col1 int(10) comment ‘[COLOR=#FF0000]呵呵’” D=test02,t=test02 --execute No slaves found. See --recursion-method if host rhel01 has slaves. Not checking slave lag because no slaves were found and --check-slave-lag was not specified. 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 `test02`.`test02`… Creating new table… CREATE TABLE `test02`.`_test02_new` ( `id` int(11) NOT NULL DEFAULT ‘0’, [COLOR=#FF0000]`name` varchar(10) DEFAULT NULL COMMENT ‘??’, [COLOR=#FF0000]`col1` int(10) DEFAULT NULL COMMENT ‘??1’, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 Created new table test02.\_test02\_new OK. Altering new table… [COLOR=#FF0000]ALTER TABLE `test02`.`_test02_new` modify column col1 int(10) comment ‘呵呵’ Altered `test02`.`_test02_new` OK. 2017-10-12T17:45:31 Creating triggers… CREATE TRIGGER `pt_osc_test02_test02_del` AFTER DELETE ON `test02`.`test02` FOR EACH ROW DELETE IGNORE FROM `test02`.`_test02_new` WHERE `test02`.`_test02_new`.`id` \<=\> OLD.`id` CREATE TRIGGER `pt_osc_test02_test02_upd` AFTER UPDATE ON `test02`.`test02` FOR EACH ROW BEGIN DELETE IGNORE FROM `test02`.`_test02_new` WHERE !(OLD.`id` \<=\> NEW.`id`) AND `test02`.`_test02_new`.`id` \<=\> OLD.`id`;REPLACE INTO `test02`.`_test02_new` (`id`, `name`, `col1`) VALUES (NEW.`id`, NEW.`name`, NEW.`col1`);END CREATE TRIGGER `pt_osc_test02_test02_ins` AFTER INSERT ON `test02`.`test02` FOR EACH ROW REPLACE INTO `test02`.`_test02_new` (`id`, `name`, `col1`) VALUES (NEW.`id`, NEW.`name`, NEW.`col1`) 2017-10-12T17:45:31 Created triggers OK. 2017-10-12T17:45:31 Copying approximately 1 rows… INSERT LOW\_PRIORITY IGNORE INTO `test02`.`_test02_new` (`id`, `name`, `col1`) SELECT `id`, `name`, `col1` FROM `test02`.`test02` LOCK IN SHARE MODE /_pt-online-schema-change 66382 copy table_/ 2017-10-12T17:45:31 Copied rows OK. 2017-10-12T17:45:31 Analyzing new table… 2017-10-12T17:45:31 Swapping tables… RENAME TABLE `test02`.`test02` TO `test02`.`_test02_old`, `test02`.`_test02_new` TO `test02`.`test02` 2017-10-12T17:45:31 Swapped original and new tables OK. 2017-10-12T17:45:31 Dropping old table… DROP TABLE IF EXISTS `test02`.`_test02_old` 2017-10-12T17:45:31 Dropped old table `test02`.`_test02_old` OK. 2017-10-12T17:45:31 Dropping triggers… DROP TRIGGER IF EXISTS `test02`.`pt_osc_test02_test02_del`; DROP TRIGGER IF EXISTS `test02`.`pt_osc_test02_test02_upd`; DROP TRIGGER IF EXISTS `test02`.`pt_osc_test02_test02_ins`; 2017-10-12T17:45:31 Dropped triggers OK. Successfully altered `test02`.`test02`. You have new mail in /var/spool/mail/root [root@rhel01 ~]# mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 73 Server version: 5.6.27-log MySQL Community Server (GPL) Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the current input statement. mysql\> use test02; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql\> show create table test02; ±-------±----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | ±-------±----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | test02 | CREATE TABLE “test02” ( “id” int(11) NOT NULL DEFAULT ‘0’, [COLOR=#FF0000]“name” varchar(10) DEFAULT NULL COMMENT ‘??’, “col1” int(10) DEFAULT NULL COMMENT ‘呵呵’, PRIMARY KEY (“id”) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 | ±-------±----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec)