在进行mysql复制过程中,会出现数据重复的现象,怎样利用mysql 过滤重复的数据呢?本文将提供详细的解决方法,需要了解的朋友可以参考下
1、replicate_do_db 和 replicate_ignore_db 不要同时出现。容易出现混淆。也是毫无意义的。Replicate_Do_DB: db1
Replicate_Ignore_DB: db2
statement模式:
使用use 语句
use db1;insert into tb1 values (1);
use db2;insert into tb2 values (2);
以上在slave上均能正确复制,tb1 有数据,tb2没有数据。
不使用use 语句
insert into db1.tb1 values (11);
insert into db2.tb2 values (11);
结果tb1没有数据,tb2也没有数据(按照文档上来讲,应该有的)
row模式:
无论是否使用use 语句,均能正确复制
小结:对于statement模式,SQL语句必须使用use 语句,并设置设置多个replicate_do_db来复制多个DB。
2、只进行表级别过滤的时候,对于statement模式,无论是否使用use语句,均能正确复制。row模式也是可以的。(表名它匹配的表的全名:数据库名+表名)
replicate_do_table=db1.tb1
statement模式:
use db1; insert into tb1 values (22);
insert into db1.tb1 values (22);
两者的复制结果一致。
(同样do 和 ignore 不要混用,除非出现过滤DB的情况)
3、有DB过滤规则的时候,statment模式必须使用USE语句,不能出现 db.表名,db.视图,db.存储程序这样的形式。row模式完胜!
replicate-ignore-db = db1
replicate-do-table = db2.tbl2
USE db1;
INSERT INTO db2.tbl2 VALUES (1);
row模式下,
默认DB不是db1,所以跳过第一条规则,执行表的规则,行被插入
statement模式下,
insert 语句被忽略,表的过滤规则已经在DB级别停止,所以没有做检查。

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