MySQL slow_log日志表出现非法字段值

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背景

从 MySQL.slow_log 获取慢查询日志很慢，该表是 csv 表，没有索引。
想添加索引来加速访问，而 csv 引擎不能添加索引（csv 引擎存储是以逗号分割的文本来存储的），只能改存储引擎来添加索引了

MySQL 中日志表 slow_log 和 general_log 主要特点

• 日志表只能是 CSV 和 MYISAM 存储引擎
• 更改日志表的存储引擎必须先停止使用该日志表
• 日志表中的数据不记录 binlog
• 锁表语句 FTWRL 和 lock tables、read_only 对日志表无效
• 用户不能对日志表进行 DML 操作，只能被 mysql 自己写入数据

CREATE TABLE slow_log (
start_time timestamp(6) NOT NULL DEFAULT CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6),
user_host mediumtext NOT NULL,
query_time time(6) NOT NULL,
lock_time time(6) NOT NULL,
rows_sent int(11) NOT NULL,
rows_examined int(11) NOT NULL,
db varchar(512) NOT NULL,
last_insert_id int(11) NOT NULL,
insert_id int(11) NOT NULL,
server_id int(10) unsigned NOT NULL,
sql_text mediumblob NOT NULL,
thread_id bigint(21) unsigned NOT NULL
) ENGINE=CSV DEFAULT CHARSET=utf8 COMMENT=’Slow log’

ALTER TABLE mysql.slow_log ENGINE = MyISAM;
ERROR 1292 (22007) at line 1: Incorrect time value: ‘838:59:59.305999’ for column ‘query_time’ at row 320264n

slow_log.csv 文件

“2019-03-05 15:29:56.102276″,”xxxx[xxxx] @ [10.230.123.134]”,”838:59:59.305999″,”00:00:00.000000″,0,0,””,0,0,2112034892,”Binlog Dump GTID”,413317

无法访问该记录

mysql> select * from mysql.slow_log where query_time like ‘838:59:59%’;
ERROR 1194 (HY000): Table ‘slow_log’ is marked as crashed and should be repaired
mysql>
mysql> check table mysql.slow_log;
+—————-+——-+———-+———-+
| Table | Op | Msg_type | Msg_text |
+—————-+——-+———-+———-+
| mysql.slow_log | check | status | OK |
+—————-+——-+———-+———-+

能正常访问其它记录

select * from mysql.slow_log limit 1\G
*************************** 1. row ***************************
start_time: 2018-09-08 13:14:51.688722
user_host: universe_op[universe_op] @ [127.0.0.1]
query_time: 00:00:01.501843
lock_time: 00:00:00.000000
rows_sent: 0
rows_examined: 0
db:
last_insert_id: 0
insert_id: 0
server_id: 2112034892
sql_text: COMMIT
thread_id: 6

尝试复现
mysql> create table test_time6(time time(6) not null) engine=csv;
Query OK, 0 rows affected (0.23 sec)

mysql>
mysql>
mysql> insert into test_time6 values(‘838:59:59.305999’);
ERROR 1292 (22007): Incorrect time value: ‘838:59:59.305999’ for column ‘time’ at row 1
mysql>
mysql>
mysql>

无法复现，提示插入的该 time 值非法。mysql 自身是怎么把该值插入 slow_log 表中的了？sql_mode 也没有修改过

修改 sql_mode 后尝试复现
mysql> show global variables like ‘%sql_mode%’;
+—————+——————————————————————————————————————————————-+
| Variable_name | Value |
+—————+——————————————————————————————————————————————-+
| sql_mode | ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+—————+——————————————————————————————————————————————-+

mysql>
mysql> set global sql_mode =”ONLY_FULL_GROUP_BY,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION”;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql>
mysql> insert into test_time6 values(‘838:59:59.305999’);
ERROR 1292 (22007): Incorrect time value: ‘838:59:59.305999’ for column ‘time’ at row 1
mysql>
mysql> show global variables like ‘%sql_mode%’;
+—————+———————————————————————————————————————–+
| Variable_name | Value |
+—————+———————————————————————————————————————–+
| sql_mode | ONLY_FULL_GROUP_BY,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+—————+———————————————————————————————————————–+
1 row in set (0.00 sec)

修改 sql_mode，去掉 STRICT_TRANS_TABLES 后，也无法插入该非法 time 值

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