--需要归档的数据量mysql admin@192.168.58.3:employees>selectcount(*)fromemployeeswherefirst_name='Anneke';+----------+|count(*)|+----------+|225|+----------+1rowinsetTime:0.025s--执行归档操作# pt-archiver--source h=192.168.
进入目录后,确保自己已经关闭了Mysql的服务:net stop mysql 关闭Mysql服务之后,继续在D:\mysql-8.0.19-winx64\bin目录下进行操作: 输入 mysqld --console --skip-grant-tables --shared-memory 1 在输入这行代码之后,如下显示,我们就已经成功跳过Mysql的密码登录了: 第三步:无密码方式进入Mysql 在上述步骤之后,...
delete[low_priority][quick][ignore]fromtbl_name[partition (partition_name [, partition_name]...)][where where_condition][order by ...][limit row_count] -- 会发现并无表别名的使用 MySql 8.0版本单表delete语法如下: delete[low_priority][quick][ignore]fromtbl_name[[as]tbl_alias][partition (...
sess1 mysql > delete from t where a=3 and b=3 ; Query OK, 1 row affected (0.00 sec) sess2 mysql >update t set c=6 where a=6 and b=6 and c=3; sess1 mysql >insert into t(a,b,c) values(3,3,5); --产生锁等待 insert (3,3,5) 申请lock S 被sess2 delete 持有的Lock X...
LOCK WAIT 18 lock struct(s), heap size 1136, 58 row lock(s), undo log entries 41 MySQL thread id 298, OS thread handle 140425685493504, query id 5479767 172.18.70.114 root updating delete from session where id in (x'B41D1ACB485A4E599A687E4AB1C36648' , x'8B2845485D584A3EB38B6D7143...
MySQL5.6 开始采用 Inplace 方式重建表,Alter 期间,支持 DML 查询和更新操作,语句为 alter table t engine=innodb, ALGORITHM=inplace;之所以支持 DML 更新操作,是因为数据拷贝期间会将 DML 更新操作记录到 Row log 中。 重建过程中最耗时的就是拷贝数据的过程,这个过程中支持 DML 查询和更新操作,对于整个 DDL ...
[Err] 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'lock in share mode' at line 1 1. 2. 加上共享锁后 ,也提示错误信息了,通过查询资料才知道,对于update,insert,delete语句会自动加排它锁的原...
row in set (0.01 sec) #重置状态变量计数 mysql> flush status; Query OK, 0 rows affected (0.01 sec) mysql> select id, age ,phone from user where name like 'lyn12%'; Empty set (0.05 sec) mysql> explain select id, age ,phone from user where name like 'lyn12%'; +---+---+--...
mysql tables in use 1, locked 1 LOCK WAIT 2 lock struct(s), heap size 360, 1 row lock(s) MySQL thread id 3525577, OS thread handle 0x7f896cc4b700, query id 780039657 localhost root updating delete from ty where a=5 *** (1) WAITING FOR THIS LOCK TO BE GRANTED: ...
select * from t_table_1 where task_id in (select id from t_table_2 where uid = #{uid}) 1. 回到这条简单sql,包含子查询,按照我们的理解,mysql应该是先执行子查询:select id from t_table_2 where uid = #{uid},然后再执行外部查询:select * from t_table_1 where task_id in(),但这不一...