一、实例演示1
模拟主从库数据不一致环境：
192.168.0.39 master库:
mysql> select * from test01.frame01;;
+----+-----------+------------------------------------------+
| id | parent_id | dsn |
+----+-----------+------------------------------------------+
| 1 | 1 | 192.168.0.22,u=pt22,p=ptchecksums,P=3307 |
| 2 | 2 | 192.168.0.33,u=pt33,p=ptchecksums,P=3308 |
+----+-----------+------------------------------------------+
2 rows in set (0.00 sec)
192.168.0.39 slave库:
mysql> update frame01 set dsn='192.168.0.55,u=umaaa,p=ptchsyeudew,P=3310' where id=1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> update frame01 set dsn='192.168.0.66,u=umbbb,p=ptchsyeudew,P=3311' where id=2;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from frame01;
+----+-----------+-------------------------------------------+
| id | parent_id | dsn |
+----+-----------+-------------------------------------------+
| 1 | 1 | 192.168.0.55,u=umaaa,p=ptchsyeudew,P=3310 |
| 2 | 2 | 192.168.0.66,u=umbbb,p=ptchsyeudew,P=3311 |
+----+-----------+-------------------------------------------+pt-table-sync校验修复数据具体指令：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=test01 --tables=frame01 --replicate=percona.checksums --print
REPLACE INTO `test01`.`frame01`(`id`, `parent_id`, `dsn`) VALUES ('1', '1', '192.168.0.22,u=pt22,p=ptchecksums,P=3307') /*percona-toolkit src_db:test01 src_tbl:frame01 src_dsn:P=3306,h=192.168.0.39,p=...,u=ptsum dst_db:test01 dst_tbl:frame01 dst_dsn:P=3306,h=192.168.0.11,p=...,u=ptsum lock:1 transaction:1 changing_src:percona.checksums replicate:percona.checksums bidirectional:0 pid:176411 user:root host:kusou-es11*/;
REPLACE INTO `test01`.`frame01`(`id`, `parent_id`, `dsn`) VALUES ('2', '2', '192.168.0.33,u=pt33,p=ptchecksums,P=3308') /*percona-toolkit src_db:test01 src_tbl:frame01 src_dsn:P=3306,h=192.168.0.39,p=...,u=ptsum dst_db:test01 dst_tbl:frame01 dst_dsn:P=3306,h=192.168.0.11,p=...,u=ptsum lock:1 transaction:1 changing_src:percona.checksums replicate:percona.checksums bidirectional:0 pid:176411 user:root host:kusou-es11*/;提示： 命令末尾的--print的指令是打印出需要修复数据的命令，不执行命令。
pt-table-sync 修复主从库的表frame01数据 ，使主从库表frame01数据一致：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=test01 --tables=frame01 --replicate=percona.checksums --execute
[root@kusou-es11 ~]# 提示： 命令末尾的 --execute 的指令是执行修复数据的指令，使master库mysql.user表和slave库的mysql.user表数据一致
pt-table-checksum 检测主从库的表frame01数据一致 （因为 DIFFS =0 ）
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-checksum h=192.168.0.39,u=ptsum,p='ptchecksums',P=3306 --databases=test01 --tables=frame01 --replicate=percona.checksums --no-check-binlog-format --nocheck-replication-filters
Checking if all tables can be checksummed ...
Starting checksum ...
TS ERRORS DIFFS ROWS DIFF_ROWS CHUNKS SKIPPED TIME TABLE
06-15T13:41:47 0 0 2 0 1 0 0.316 test01.frame01slave库查看，数据和主库一致
mysql> select * from test01.frame01;
+----+-----------+------------------------------------------+
| id | parent_id | dsn |
+----+-----------+------------------------------------------+
| 1 | 1 | 192.168.0.22,u=pt22,p=ptchecksums,P=3307 |
| 2 | 2 | 192.168.0.33,u=pt33,p=ptchecksums,P=3308 |
+----+-----------+------------------------------------------+
2 rows in set (0.00 sec)提示：需要注意的是，需要同步的表上必须要有主键或者唯一索引，否则会出错。
同时，pt-table-sync 修复数据时，会造成锁表，要在业务低峰期来修复主库的数据
对找到的主从不一致的行，采用replace into语句，在主库执行一遍以生成该行全量的binlog，并同步到从库，这会以主库数据为基准来修复从库；
对于主库有的行而从库没有的行，采用replace在主库上插入(必须不能是×××ert)；
对于从库有而主库没有的行，通过在主库执行delete来删除(pt-table-sync强烈建议所有的数据修复都只在主库进行，而不建议直接修改从库数据；但是也有特例，以后面会讲到)。
二、实例演示2
在slave库上的mysql user表上，新建一个用户 qdtets@'192.168.0.%' 模拟master和slave库数据不一致
grant all on *.* to qdtets@'192.168.0.%' identified by 'DHWUOEdwerer';flush privileges;[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-checksum h=192.168.0.39,u=ptsum,p='ptchecksums',P=3306 --databases=mysql --replicate=percona.checksums --no-check-binlog-format --nocheck-replication-filters
Checking if all tables can be checksummed ...
Starting checksum ...
TS ERRORS DIFFS ROWS DIFF_ROWS CHUNKS SKIPPED TIME TABLE
06-15T13:32:27 0 0 0 0 1 0 0.317 mysql.columns_priv
06-15T13:32:28 0 0 2 0 1 0 0.318 mysql.db
06-15T13:32:28 0 0 2 0 1 0 0.316 mysql.engine_cost
06-15T13:32:28 0 0 0 0 1 0 0.317 mysql.event
06-15T13:32:29 0 0 0 0 1 0 0.316 mysql.func
06-15T13:32:29 0 0 41 0 1 0 0.317 mysql.help_category
06-15T13:32:29 0 0 699 0 1 0 0.318 mysql.help_keyword
06-15T13:32:30 0 0 1413 0 1 0 0.319 mysql.help_relation
06-15T13:32:30 0 0 643 0 1 0 0.325 mysql.help_topic
06-15T13:32:30 0 0 0 0 1 0 0.316 mysql.ndb_binlog_index
06-15T13:32:31 0 0 0 0 1 0 0.316 mysql.plugin
06-15T13:32:31 0 1 48 0 1 0 0.317 mysql.proc
06-15T13:32:31 0 0 0 0 1 0 0.317 mysql.procs_priv
06-15T13:32:32 0 0 1 0 1 0 0.317 mysql.proxies_priv
06-15T13:32:32 0 0 6 0 1 0 0.317 mysql.server_cost
06-15T13:32:32 0 0 0 0 1 0 0.316 mysql.servers
06-15T13:32:33 0 0 2 0 1 0 0.317 mysql.tables_priv
06-15T13:32:33 0 0 0 0 1 0 0.316 mysql.time_zone
06-15T13:32:33 0 0 0 0 1 0 0.316 mysql.time_zone_leap_second
06-15T13:32:33 0 0 0 0 1 0 0.316 mysql.time_zone_name
06-15T13:32:34 0 0 0 0 1 0 0.318 mysql.time_zone_transition
06-15T13:32:34 0 0 0 0 1 0 0.317 mysql.time_zone_transition_type
**06-15T13:32:34 0 1 6 1 1 0 0.319 mysql.user**在slave库上pt-table-sync 修复数据：
扫描二维码关注公众号，回复：
6500337 查看本文章
slave库上操作：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=mysql --tables=user --replicate=percona.checksums --print
Access denied for user 'ptsum'@'192.168.0.%' to database 'mysql' [for Statement "LOCK TABLES `mysql`.`user` WRITE"] at line 6172 while doing mysql.user on 192.168.0.11报错，提示没lock tables 权限
解决办法：登录master库重新授权，添加lock tables权限
grant update,×××ert,select,create,drop,delete,index,execute,lock tables,super,process,replication slave on *.* to ptsum@'192.168.0.%' identified by 'ptchecksums'; flush privileges;[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=mysql --tables=user --replicate=percona.checksums --print
DELETE FROM `mysql`.`user` WHERE `host`='192.168.0.%' AND `user`='qdtets' LIMIT 1 /*percona-toolkit src_db:mysql src_tbl:user src_dsn:P=3306,h=192.168.0.39,p=...,u=ptsum dst_db:mysql dst_tbl:user dst_dsn:P=3306,h=192.168.0.11,p=...,u=ptsum lock:1 transaction:0 changing_src:percona.checksums replicate:percona.checksums bidirectional:0 pid:137319 user:root host:kusou-es11*/;提示： 命令末尾的--print的指令是打印出需要修复数据的命令，不执行命令。
使用pt-table-checksum检测mysql的user表，DIFFS =1 事实证明master和slave的mysql user表数据确实不一致：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-checksum h=192.168.0.39,u=ptsum,p='ptchecksums',P=3306 --databases=mysql --tables=user --no-check-binlog-format --nocheck-replication-filters
Checking if all tables can be checksummed ...
Starting checksum ...
TS ERRORS DIFFS ROWS DIFF_ROWS CHUNKS SKIPPED TIME TABLE
06-15T09:58:37 0 1 6 1 1 0 0.318 mysql.user执行修复命令pt-table-sync 修复master和slave的mysql user表数据：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=mysql --tables=user --replicate=percona.checksums --execute
[root@kusou-es11 ~]# 提示： 命令末尾的 --execute 的指令是执行修复数据的指令，使master库mysql.user表和slave库的mysql.user表数据一致
slave库上检查master库的mysql.user表 和slave库的mysql.user 表数据是否一致：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-checksum h=192.168.0.39,u=ptsum,p='ptchecksums',P=3306 --databases=mysql --tables=user --no-check-binlog-format --nocheck-replication-filters
Checking if all tables can be checksummed ...
Starting checksum ...
TS ERRORS DIFFS ROWS DIFF_ROWS CHUNKS SKIPPED TIME TABLE
06-15T09:46:52 0 0 6 0 1 0 0.319 mysql.user可以看到DIFFS =0 ，说明数据已经修复完成
三、实例演示3
将master 上的所有数据同步到slave：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync --execute h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=mysql --tables=user h=192.168.0.11,u=ptsum,p='ptchecksums',P=3306 --no-check-slave --print
DELETE FROM `mysql`.`user` WHERE `host`='10.0.0.1' AND `user`='dhrue' LIMIT 1 /*percona-toolkit src_db:mysql src_tbl:user src_dsn:P=3306,h=192.168.0.39,p=...,u=ptsum dst_db:mysql dst_tbl:user dst_dsn:P=3306,h=192.168.0.11,p=...,u=ptsum lock:0 transaction:0 changing_src:0 replicate:0 bidirectional:0 pid:12565 user:root host:kusou-es11*/;将master 上的所有数据同步到slave1和slave2：
[root@kusou-es11 ~]# /usr/local/percona-toolkit/bin/pt-table-sync --execute h=192.168.0.39,u=ptsum,p=ptchecksums,P=3306 --databases=mysql --tables=user h=192.168.0.11,u=ptsum,p='ptchecksums',P=3307 h=192.168.0.22,u=ptsum,p='ptchecksums',P=3308 --no-check-slave --print对pt-table-checksum和pt-table-sync这一组工具进行了最简单的测试，其实运行这一组命令不一定需要在主从结构的主库上进行，网段内的任何服务器都可以运行，前提就是安装好这套工具就好。
四、原理介绍
pt-table-checksum/pt-table-sync原理介绍可以参考如下博文：
http://blog.sina.com.cn/s/blog_a1e9c7910102vnsd.html