pt-find - Find MySQL tables and execute actions, like GNU find.
用法：
pt-find [OPTION...] [DATABASE...]
例子：
找出创建于一天之前，并且是myisam存储引擎的表
[root@goolen ~]# pt-find --ctime +1 --engine MyISAM -uroot -proot
`mysql`.`db`
`mysql`.`event`
`mysql`.`func`
`mysql`.`help_category`
`mysql`.`help_keyword`
`mysql`.`help_relation`
`mysql`.`help_topic`
`mysql`.`host`
`mysql`.`ndb_binlog_index`
`mysql`.`plugin`
`mysql`.`proc`
`mysql`.`procs_priv`
`mysql`.`proxies_priv`
`mysql`.`servers`
`mysql`.`tables_priv`
`mysql`.`time_zone`
`mysql`.`time_zone_leap_second`
`mysql`.`time_zone_name`
`mysql`.`time_zone_transition`
`mysql`.`time_zone_transition_type`
`mysql`.`user`
找出goolen库中的innodb引擎的表，并且把他们转换为myisam表：
mysql> select table_name,engine from information_schema.tables where table_schema='goolen';
+-----------------+--------+
| table_name | engine |
+-----------------+--------+
| a | InnoDB |
| b | InnoDB |
| c | InnoDB |
| g1 | InnoDB |
| topic_indicator | InnoDB |
+-----------------+--------+
[root@goolen ~]# pt-find --engine InnoDB --exec "ALTER TABLE %D.%N ENGINE=MyISAM" -uroot -proot goolen
mysql> select table_name,engine from information_schema.tables where table_schema='goolen';
+-----------------+--------+
| table_name | engine |
+-----------------+--------+
| a | MyISAM |
| b | MyISAM |
| c | MyISAM |
| g1 | MyISAM |
| topic_indicator | MyISAM |
+-----------------+--------+
找出goolen库中的空表，然后删除：
mysql> use goolen;
Database changed
mysql> show tables;
+------------------+
| Tables_in_goolen |
+------------------+
| a |
| b |
| c |
| g1 |
| topic_indicator |
+------------------+
5 rows in set (0.00 sec)
[root@goolen ~]# pt-find --empty goolen --exec-plus "DROP TABLE %s"
mysql> show tables;
+------------------+
| Tables_in_goolen |
+------------------+
| g1 |
+------------------+
1 row in set (0.00 sec)
找出goolen库中size大于200M的表
[root@goolen goolen]# ll -h bigsize_table.*
-rw-rw---- 1 mysql mysql 9.4K Dec 2 16:52 bigsize_table.frm
-rw-rw---- 1 mysql mysql 420M Dec 2 16:54 bigsize_table.ibd
[root@goolen ~]# pt-find --tablesize +200M -uroot -proot goolen
`goolen`.`bigsize_table`
Find all tables and print their total data and index size, and sort largest tables first (sort is a different program, by the way).
列出所有的表，包括表的总行数和索引的size，并按总数倒序排序（排序操作有系统命令sort完成，pt-find本身没排序功能）
[root@goolen ~]# pt-find --printf "%T\t%D.%N\n" -uroot -proot | sort -rn
425639936 `goolen`.`bigsize_table`
461592 `mysql`.`help_topic`
108816 `mysql`.`help_keyword`
32768 `test`.`goolen3`
32768 `test`.`goolen2`
27675 `mysql`.`help_relation`
25150 `mysql`.`help_category`
16384 `test`.`t1`
16384 `test`.`goolen`
6880 `mysql`.`db`
6506 `mysql`.`proxies_priv`
。。。
。。。
As above, but this time, insert the data back into the database for posterity:
列出所有的表，把输出信息保存到goolen库里的tblsize表里：
mysql> create table tblsize(db varchar(20),tbl varchar(35) ,size int);
Query OK, 0 rows affected (0.12 sec)
[root@goolen ~]# pt-find --noquote --exec "INSERT INTO goolen.tblsize(db, tbl, size) VALUES('%D', '%N', %T)" -uroot -proot
mysql> select * from tblsize;
+--------------------+-------------------------------------+-----------+
| db | tbl | size |
+--------------------+-------------------------------------+-----------+
| goolen | bigsize_table | 425639936 |
| goolen | g1 | 2108 |
| goolen | tblsize | 16384 |
| mysql | columns_priv | 4096 |
| mysql | db | 6880 |
| mysql | event | 2048 |
| mysql | func | 1024 |
| mysql | general_log | 0 |
+--------------------+-------------------------------------+-----------+
参数说明：
--ask-pass
Prompt for a password when connecting to MySQL.
连接的时候提示输出密码
例：
[root@goolen ~]#
[root@goolen ~]# pt-find --printf "%T\t%D.%N\n" -uroot --ask-pass goolen
Enter password:
425639936 `goolen`.`bigsize_table`
2108 `goolen`.`g1`
16384 `goolen`.`tblsize`
--case-insensitive
Specifies that all regular expression searches are case-insensitive.
例：
默认匹配区分大小写，innodb全部小写，没有输出匹配信息
[root@goolen ~]# pt-find --engine innodb --printf "ALTER TABLE %D.%N ENGINE=MyISAM" -uroot -proot goolen
指定忽略大小写：
[root@goolen ~]# pt-find --engine innodb --printf "ALTER TABLE %D.%N ENGINE=MyISAM" -uroot -proot goolen --case-insensitive
ALTER TABLE `goolen`.`bigsize_table` ENGINE=MyISAMALTER TABLE `goolen`.`tblsize` ENGINE=MyISAM
[root@goolen ~]# pt-find --engine InnoDB --printf "ALTER TABLE %D.%N ENGINE=MyISAM" -uroot -proot goolen
ALTER TABLE `goolen`.`bigsize_table` ENGINE=MyISAMALTER TABLE `goolen`.`tblsize` ENGINE=MyISAM
[root@goolen ~]#
