MySQL查询执行中的事务

-- 查看msyql事务隔离级别

show SESSION variables like '%isolation%';

--慢日志 查询死锁

SHOW VARIABLES LIKE '%slow_query_log%';--查看慢日志文件地址

--慢日志打开

set global slow_query_log='ON'

--慢日志秒数

set global long_query_time = 3;

SET GLOBAL sync_binlog=1000; 

--binlog优化同步的时间

show variables like 'sync_binlog';

SET GLOBAL sync_binlog=1000 

#查看死锁

select * from performance_schema.data_locks;

#查看死锁等待时间

select * from performance_schema.data_lock_waits;

#查询最近的锁

show engine innodb status;

#查询事务

SELECT * FROM INFORMATION_SCHEMA.INNODB_TRX;

拼接sql 修改字符集

SELECT

CONCAT( "ALTER TABLE `", TABLE_NAME, "` CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;" ) AS target_tables

FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = "88435929303281664"