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 1G *************************** 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
