mysql checksum MySQL master-slave overall data consistency verification, temporarily does not include incremental data verification
The working principle is as follows
step1: FLUSH TABLES WITH READ LOCK
step2: SHOW MASTER STATUS && SELECT @@GLOBAL.GTID_EXECUTED
step4: init pool SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ START TRANSACTION /*!40100 WITH CONSISTENT SNAPSHOT */ conChan <- con
step5: checksum table table_name
数据一致性检查原理：主要依赖MySQL自带的快照事务及checksum table命令来实现，主要实现步骤如下
步骤1：执行FLUSH TABLES WITH READ LOCK，获取全局一致性位点
步骤2：获取binlog位点信息SHOW MASTER STATUS && SELECT @@GLOBAL.GTID_EXECUTED
步骤3：初始化主从数据库连接池，主从执行SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ && SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ，获取一致性位点的连接放入主从连接池chan
步骤4：通过连接池chan实现并发checksum