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過小

處理思路：

① 通過hints，增大N值（文檔說，在hints用法中，將N改為0為無限制，但我測下來不生效，可設置成一個較大值如999999解決）

SELECT /*+ MAX_EXECUTION_TIME(N) */ * FROM t1 LIMIT 100000;

② 修改max_execution_time值，將該值設置為較大一個值，或設置為0（不限制）

附錄：

該參數5.7.8被添加，單位為ms，動態參數，默認為0，設置為0時意味著SELECT超時不被設置（不限制超時時間）。不作用于存儲過程中的SELECT語句，并且只作用于只讀的SELECT，如INSERT ... SELECT ... 是不被作用的。

for more information:

      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：

該view引用了無效的表，列，函數或者定義者。

處理思路：

可以根據報錯信息，進入db，執行SHOW CREATE VIEW $view_name/G，查看該view的定義，逐一檢查該view的基表，列，或相關函數與用戶是否具有相關權限。考慮重建或刪除視圖。

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

原因：

創建view時，使用UNION時存在非法的排序規則組合。

處理思路：

檢查該視圖定義，檢查字符集，考慮重建或刪除視圖。

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：

該視圖的定義者$user@$host不存在。

處理思路：

檢查mysql.user表，確認用戶是否存在，考慮重建或刪除視圖。

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：

從lower_case_table_names的0設置成1，導致部分原來含有大寫字母的庫表“找不到”。

處理思路：

將lower_case_table_names設置回0。

若有必須將lower_case_table_names設置為1，需先設置為0，并將含有大寫字母的庫表改成小寫，再設置為1。

原因二（MySQL 5.5及以下版本可能出現）：

表損壞導致該表找不到（InnoDB）。frm和ibd文件都在，但無法SHOW CREATE TABLE xxx/G

error log一則：

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.

處理思路：

從完整備份+binlog還原，對于有主或從的實例，可通過物理備份還原。

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

原因：

默認的max_allowed_packet過小

處理思路：

在mysqldump時增加max_allowed_packet的大小，如mysqldump --max-allowed-packet=268435456

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

原因：

在備份該表時，表定義被修改。FLUSH TABLE WITH READ LOCK只保證數據一致性，并不保證schema不被修改。

處理思路：

備份時期不做DDL操作。

復現一：

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調換順序，則ALTER TABLE無法成功，則會等待MDL。

復現二：

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

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：

出現在表引擎為MERGE時，備份到該表時，發現該表定義存在問題。可能merge的表不存在，或者該表合并的基表包含非MyISAM引擎的表。

處理思路：

刪除或者重建該MERGE表。

復現一（merge表中定義包含了非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

復現二（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

附錄：

通過check table merge_t可以檢查是哪張表有問題，如此處是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)

通過cat表MGR定義結構文件可以檢查MERGE表的基表：

[root@host test]# pwd

/data/mysql-data/mysql57/data/test

[root@host test]# cat merge_t.MRG

t1

t2

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在拉取表定義時報錯，表損壞。

處理思路：

該損壞發生在非事務表如MyISAM，通過mysqlcheck或者repair table修復即可。

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

原因：

字典表不正確，可能是表本身損壞，也有可能是導入了其他版本的mysql schema蓋掉了字典表。

處理思路：

repair table修復，若仍無用，則可以嘗試mysql_upgrade來修復，或找到對應版本的mysql_system_tables_fix.sql來導入。

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

原因：

字典表不正確，極大可能是導入了其他版本的mysql schema蓋掉了字典表。

處理思路：

嘗試mysql_upgrade來修復，或找到對應版本的mysql_system_tables_fix.sql來導入。該報錯可能在upgrade操作之后重啟實例。

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滿了。

處理思路：

清除@@tmpdir，可以通過SELECT @@tmpdir;檢查具體目錄。

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執行過程中mysqld被關閉。

處理思路：

檢查mysqld被關閉的原因，一般常見原因是發生OOM。

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參數，缺少SUPER或REPLICATION CLIENT來執行SHOW SLAVE STATUS。

處理思路：

檢查mysqldump的用戶權限。

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參數，缺少SUPER權限使用STOP SLAVE SQL_THREAD。

處理思路：

檢查mysqldump的用戶權限。