mysqldump备份失败以及解决方法汇总

mysqldump备份失败以及解决方法汇总

1、mysqldump: Error: Query execution was interrupted, maximum statement execution time exceeded when trying to dump tablespaces
mysqldump: Error 3024: Query execution was interrupted, maximum statement execution time exceeded when dumping table $tb_name at row: xxxx

版本:
MySQL 5.7.8+
原因:
max_execution_time过小
处理思路:
① 通过hints,增大N值(文档说,在hints用法中,将N改为0为无限制,但我测下来不生效,可设置成一个较大值如999999解决)
SELECT /*+ MAX_EXECUTION_TIME(N) */ * FROM t1 LIMIT 100000;
② 修改max_execution_time值,将该值设置为较大一个值,或设置为0(不限制)
附录:
该参数5.7.8被添加,单位为ms,动态参数,默认为0,设置为0时意味着SELECT超时不被设置(不限制超时时间)。不作用于存储过程中的SELECT语句,并且只作用于只读的SELECT,如INSERT … SELECT … 是不被作用的。
for more information:
http://blog.itpub.net/29773961/viewspace-2150443/

2、mysqldump: Couldnt execute SHOW FIELDS FROM $view_name: View $db_name.$view_name references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them (1356)

原因:
该view引用了无效的表,列,函数或者定义者。
处理思路:
可以根据报错信息,进入db,执行SHOW CREATE VIEW $view_name\G,查看该view的定义,逐一检查该view的基表,列,或相关函数与用户是否具有相关权限。考虑重建或删除视图。

3、mysqldump: Couldnt execute show create table $view_name: Illegal mix of collations for operation UNION (1271)

原因:
创建view时,使用UNION时存在非法的排序规则组合。
处理思路:
检查该视图定义,检查字符集,考虑重建或删除视图。

4、mysqldump: Couldnt execute SHOW FIELDS FROM $view_name: The user specified as a definer ($user@$host) does not exist (1449)
mysqldump: Couldnt execute show table status like $view_name: SELECT command denied to user @% for column $col_name in table $tb_name (1143)

原因:
该视图的定义者$user@$host不存在。
处理思路:
检查mysql.user表,确认用户是否存在,考虑重建或删除视图。

5、Error: Couldnt read status information for table Income_config ()mysqldump: Couldnt execute show create table Tser_table: Table $db_name.test_table doesnt exist (1146)
mysqldump: Got error: 1049: Unknown database $db_name when selecting the database

原因一:
从lower_case_table_names的0设置成1,导致部分原来含有大写字母的库表“找不到”。
处理思路:
将lower_case_table_names设置回0。
若有必须将lower_case_table_names设置为1,需先设置为0,并将含有大写字母的库表改成小写,再设置为1。

原因二(MySQL 5.5及以下版本可能出现):
表损坏导致该表找不到(InnoDB)。frm和ibd文件都在,但无法SHOW CREATE TABLE xxx\G
error log一则:

170820 17:43:17 [Note] Event Scheduler: scheduler thread started with id 1
170820 17:44:48 InnoDB: error: space object of table '$db_name/$tb_name',
InnoDB: space id 4335 did not exist in memory. Retrying an open.
170820 17:44:48 InnoDB: Error: tablespace id and flags in file './$db_name/$tb_name.ibd' are 0 and 0, but in the InnoDB
InnoDB: data dictionary they are 4335 and 0.
InnoDB: Have you moved InnoDB .ibd files around without using the
InnoDB: commands DISCARD TABLESPACE and IMPORT TABLESPACE?
InnoDB: Please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.5/en/innodb-troubleshooting-datadict.html
InnoDB: for how to resolve the issue.
170820 17:44:48 InnoDB: cannot calculate statistics for table $db_name/$tb_name
InnoDB: because the .ibd file is missing. For help, please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.5/en/innodb-troubleshooting.html
170820 17:44:48 [ERROR] MySQL is trying to open a table handle but the .ibd file for
table $db_name/$tb_name does not exist.
Have you deleted the .ibd file from the database directory under
the MySQL datadir, or have you used DISCARD TABLESPACE?
See http://dev.mysql.com/doc/refman/5.5/en/innodb-troubleshooting.html
how you can resolve the problem.

处理思路:
从完整备份+binlog还原,对于有主或从的实例,可通过物理备份还原。

6、mysqldump: Error 2020: Got packet bigger than max_allowed_packet bytes when dumping table $tb_name at row: xxxx

原因:
默认的max_allowed_packet过小
处理思路:
在mysqldump时增加max_allowed_packet的大小,如mysqldump –max-allowed-packet=268435456

7、mysqldump: Error 1412: Table definition has changed, please retry transaction when dumping table $tb_name at row: 0

原因:
在备份该表时,表定义被修改。FLUSH TABLE WITH READ LOCK只保证数据一致性,并不保证schema不被修改。
处理思路:
备份时期不做DDL操作。
复现一:

① session1> CREATE TABLE a (id int) ENGINE=InnoDB;
② session2> START TRANSACTION WITH CONSISTENT SNAPSHOT;
③ session1> ALTER TABLE a ADD COLUMN name varchar(32);
④ session2> SELECT * FROM a;
ERROR 1412 (HY000): Table definition has changed, please retry transaction

p.s. 如果③和④调换顺序,则ALTER TABLE无法成功,则会等待MDL。
复现二:

① session1> START TRANSACTION WITH CONSISTENT SNAPSHOT;
② session2> CREATE TABLE b (id int) ENGINE=InnoDB;
③ session1> SELECT * FROM b;
ERROR 1412 (HY000): Table definition has changed, please retry transaction

8、mysqldump: Couldnt execute show create table $tb_name: Unable to open underlying table which is differently defined or of non-MyISAM type or doesnt exist (1168)

原因:
出现在表引擎为MERGE时,备份到该表时,发现该表定义存在问题。可能merge的表不存在,或者该表合并的基表包含非MyISAM引擎的表。
处理思路:
删除或者重建该MERGE表。
复现一(merge表中定义包含了非MyISAM表):

CREATE TABLE t1(id int) ENGINE=InnoDB;
CREATE TABLE t2(id int) ENGINE=MyISAM;
CREATE TABLE merge_t(id int)ENGINE=MERGE UNION=(t1, t2);
SELECT * FROM merge_t;
ERROR 1168 (HY000): Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist

复现二(表不存在):

CREATE TABLE t1(id int) ENGINE=MyISAM;
CREATE TABLE t2(id int) ENGINE=MyISAM;
CREATE TABLE merge_t(id int)ENGINE=MERGE UNION=(t1, t2);
SELECT * FROM merge_t;
Empty set (0.00 sec)    -- 正常返回
DROP TABLE t1;
SELECT * FROM merge_t;
ERROR 1168 (HY000): Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist

附录:
通过check table merge_t可以检查是哪张表有问题,如此处是t1:

[15:20:12] root@localhost [test]> check table merge_t\G
*************************** 1. row ***************************
  Table: test.merge_t
     Op: check
Msg_type: Error
Msg_text: Table 'test.t1' is differently defined or of non-MyISAM type or doesn't exist
*************************** 2. row ***************************
  Table: test.merge_t
     Op: check
Msg_type: Error
Msg_text: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
*************************** 3. row ***************************
  Table: test.merge_t
     Op: check
Msg_type: error
Msg_text: Corrupt
3 rows in set (0.00 sec)

通过cat表MGR定义结构文件可以检查MERGE表的基表:

[root@host test]# pwd
/data/mysql-data/mysql57/data/test
[root@host test]# cat merge_t.MRG
t1
t2

9、mysqldump: Couldnt execute show create table $tb_name: Table ./$db_name/$tb_name is marked as crashed and last (automatic?) repair failed (144)
mysqldump: Couldnt execute show create table $tb_name: Table ./$db_name/$tb_name is marked as crashed and should be repaired (145)
mysqldump: Error 1194: Table throne_tower is marked as crashed and should be repaired when dumping table $tb_name at row: xxxxx

原因:
mysqldump在拉取表定义时报错,表损坏。
处理思路:
该损坏发生在非事务表如MyISAM,通过mysqlcheck或者repair table修复即可。

10、mysqldump: Couldnt execute SHOW FUNCTION STATUS WHERE Db = $db_name: Cannot load from mysql.$tb_name. The table is probably corrupted (1728)

原因:
字典表不正确,可能是表本身损坏,也有可能是导入了其他版本的mysql schema盖掉了字典表。
处理思路:
repair table修复,若仍无用,则可以尝试mysql_upgrade来修复,或找到对应版本的mysql_system_tables_fix.sql来导入。

11、mysqldump: Couldnt execute show events: Cannot proceed because system tables used by Event Scheduler were found damaged at server start (1577)

原因:
字典表不正确,极大可能是导入了其他版本的mysql schema盖掉了字典表。
处理思路:
尝试mysql_upgrade来修复,或找到对应版本的mysql_system_tables_fix.sql来导入。该报错可能在upgrade操作之后重启实例。

12、mysqldump: Error: Got error 28 from storage engine when trying to dump tablespaces
mysqldump: Couldnt execute show fields from $tb_name: Got error 28 from storage engine (1030)

原因:
@@tmpdir满了。
处理思路:
清除@@tmpdir,可以通过SELECT @@tmpdir;检查具体目录。

13、mysqldump: Lost connection to MySQL server during query (2013)
ERROR 2002 (HY000): Can’t connect to local MySQL server through socket ‘@@socket’ (111)

原因:
mysqldump执行过程中mysqld被关闭。
处理思路:
检查mysqld被关闭的原因,一般常见原因是发生OOM。

14、mysqldump: Couldn’t execute ‘SHOW SLAVE STATUS’: Access denied; you need (at least one of) the SUPER, REPLICATION CLIENT privilege(s) for this operation (1227)

原因:
mysqldump加了–dump-slave参数,缺少SUPER或REPLICATION CLIENT来执行SHOW SLAVE STATUS。
处理思路:
检查mysqldump的用户权限。

15、mysqldump: Couldn’t execute ‘STOP SLAVE SQL_THREAD’: Access denied for user ‘dump’@’localhost’ (using password: YES) (1045)

原因:
mysqldump加了–dump-slave参数,缺少SUPER权限使用STOP SLAVE SQL_THREAD。
处理思路:
检查mysqldump的用户权限。

标签:备份MySQL 发布于:2019-10-28 02:48:22