MySQL-Utilities：mysqldiff

园子看到使用MySQL对比数据库表结构，参考测试发现

mysql> use test;
create table test1
(id int not null primary key,
a varchar(10) not null,
b varchar(10),
c varchar(10) comment 'c',
d int
)
ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='test1';
create table test2
(id int not null ,
a varchar(10),
b varchar(5),
c varchar(10),
D int
)
ENGINE=myisam DEFAULT CHARSET=utf8 COMMENT='test2';

[root@localhost uest]# mysqldiff --server1=root:mysql5635@localhost:3306 --server2=root:mysql5635@localhost:3306 --changes-for=server2 --show-reverse --difftype=sql test.test1:test.test2
bash: mysqldiff: command not found
[root@localhost uest]# 

搜索才知道mysqldiff工具是官方MySQL-Utilities工具集的一个脚本。mysqldiff用来比较对象的定义是否相同并显示不同的地方，mysqldiff 是通过对象名称来进行比较的。
系统环境紧接上一篇，因此需下载相应的rpm包

[root@localhost tools]# wget https://cdn.mysql.com//Downloads/MySQLGUITools/mysql-utilities-1.6.5-1.el6.noarch.rpm
[root@localhost tools]# rpm -ivh mysql-utilities-1.6.-.el6.noarch.rpm
warning: mysql-utilities-1.6.-.el6.noarch.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
error: Failed dependencies:
    mysql-connector-python >= 2.0. is needed by mysql-utilities-1.6.-.el6.noarch
[root@localhost tools]#

需要依赖文件

[root@localhost tools]# wget https://cdn.mysql.com//Downloads/Connector-Python/mysql-connector-python-2.1.5-1.el6.i686.rpm
[root@localhost tools]# rpm -ivh mysql-connector-python-2.1.-.el6.i686.rpm
warning: mysql-connector-python-2.1.-.el6.i686.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                ########################################### [%]
   :mysql-connector-python ########################################### [%]
[root@localhost tools]# rpm -ivh mysql-utilities-1.6.-.el6.noarch.rpm
warning: mysql-utilities-1.6.-.el6.noarch.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                ########################################### [%]
   :mysql-utilities        ########################################### [%]
[root@localhost tools]#

然后就可以执行mysqldiff命令了

[root@localhost tools]# mysqldiff --server1=root:mysql5635@localhost:3306 --server2=root:mysql5635@localhost:3306 --changes-for=server2 --skip-table-options --show-reverse --difftype=sql test.test1:test.test2
# WARNING: Using a password on the command line interface can be insecure.
# server1 on localhost: ... connected.
# server2 on localhost: ... connected.
# Comparing test.test1 to test.test2                               [FAIL]
# Transformation for --changes-for=server2:
#

ALTER TABLE `test`.`test2`
  DROP COLUMN D,
  ADD PRIMARY KEY(`id`),
  CHANGE COLUMN b b varchar() NULL,
  ADD COLUMN d int() NULL AFTER c,
  CHANGE COLUMN a a varchar() NOT NULL,
  CHANGE COLUMN c c varchar() NULL COMMENT 'c';

#
# Transformation for reverse changes (--changes-for=server1):
#
# ALTER TABLE `test`.`test1`
#   DROP PRIMARY KEY,
#   DROP COLUMN d,
#   CHANGE COLUMN b b varchar() NULL,
#   ADD COLUMN D int() NULL AFTER c,
#   CHANGE COLUMN a a varchar() NULL,
#   CHANGE COLUMN c c varchar() NULL;
#

# Compare failed. One or more differences found.
[root@localhost tools]# 

MySQL Utilities 提供一组命令行工具用于维护和管理 MySQL 服务器，可参考官方手册，或者查阅MySQL Utilities教程。