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  • [root@localhost mysql-server-5.1.73]# cp /usr/share/doc/mysql-server-5.1.73/my-large.cnf /etc/my.cnf cp: overwrite `/etc/my.cnf'? y [root@localhost mysql-server-5.1.73]# vim /etc/my.cnf ---------- #
    
    [root@localhost mysql-server-5.1.73]# cp /usr/share/doc/mysql-server-5.1.73/my-large.cnf  /etc/my.cnf
    cp: overwrite `/etc/my.cnf'? y
    [root@localhost mysql-server-5.1.73]# vim  /etc/my.cnf
    
    
    ----------
    
    
    # Example MySQL config file for large systems.
    #
    # This is for a large system with memory = 512M where the system runs mainly
    # MySQL.
    #
    # MySQL programs look for option files in a set of
    # locations which depend on the deployment platform.
    # You can copy this option file to one of those
    # locations. For information about these locations, see:
    # http://dev.mysql.com/doc/mysql/en/option-files.html
    #
    # In this file, you can use all long options that a program supports.
    # If you want to know which options a program supports, run the program
    # with the "--help" option.
    
    # The following options will be passed to all MySQL clients
    [client]
    #password       = your_password
    port            = 3306
    socket          = /var/lib/mysql/mysql.sock
    
    # Here follows entries for some specific programs
    
    # The MySQL server
    [mysqld]
    port            = 3306
    socket          = /var/lib/mysql/mysql.sock
    skip-locking
    key_buffer_size = 256M
    max_allowed_packet = 1M
    table_open_cache = 256
    sort_buffer_size = 1M
    read_buffer_size = 1M
    read_rnd_buffer_size = 4M
    myisam_sort_buffer_size = 64M
    thread_cache_size = 8
    query_cache_size= 16M
    # Try number of CPU's*2 for thread_concurrency
    thread_concurrency = 8
    
    # Don't listen on a TCP/IP port at all. This can be a security enhancement,
    # if all processes that need to connect to mysqld run on the same host.
    # All interaction with mysqld must be made via Unix sockets or named pipes.
    # Note that using this option without enabling named pipes on Windows
    # (via the "enable-named-pipe" option) will render mysqld useless!
    #
    #skip-networking
    
    # Replication Master Server (default)
    # binary logging is required for replication
    log-bin=mysql-bin
    
    # binary logging format - mixed recommended
    binlog_format=mixed
    
    # required unique id between 1 and 2^32 - 1
    # defaults to 1 if master-host is not set
    # but will not function as a master if omitted
    server-id       = 1
    
    # Replication Slave (comment out master section to use this)
    #
    # To configure this host as a replication slave, you can choose between
    # two methods :
    #
    # 1) Use the CHANGE MASTER TO command (fully described in our manual) -
    #    the syntax is:
    #
    #    CHANGE MASTER TO MASTER_HOST=<host>, MASTER_PORT=<port>,
    #    MASTER_USER=<user>, MASTER_PASSWORD=<password> ;
    #
    #    where you replace <host>, <user>, <password> by quoted strings and
    #    <port> by the master's port number (3306 by default).
    #
    #    Example:
    #
    #    CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,
    #    MASTER_USER='joe', MASTER_PASSWORD='secret';
    #
    # OR
    #
    # 2) Set the variables below. However, in case you choose this method, then
    #    start replication for the first time (even unsuccessfully, for example
    #    if you mistyped the password in master-password and the slave fails to
    #    connect), the slave will create a master.info file, and any later
    #    change in this file to the variables' values below will be ignored and
    #    overridden by the content of the master.info file, unless you shutdown
    #    the slave server, delete master.info and restart the slaver server.
    #    For that reason, you may want to leave the lines below untouched
    #    (commented) and instead use CHANGE MASTER TO (see above)
    #
    # required unique id between 2 and 2^32 - 1
    # (and different from the master)
    # defaults to 2 if master-host is set
    # but will not function as a slave if omitted
    #server-id       = 2
    #
    # The replication master for this slave - required
    #master-host     =   <hostname>
    #
    # The username the slave will use for authentication when connecting
    # to the master - required
    #master-user     =   <username>
    #
    # The password the slave will authenticate with when connecting to
    # the master - required
    #master-password =   <password>
    #
    # The port the master is listening on.
    # optional - defaults to 3306
    #master-port     =  <port>
    #
    # binary logging - not required for slaves, but recommended
    #log-bin=mysql-bin
    
    # Uncomment the following if you are using InnoDB tables
    #innodb_data_home_dir = /var/lib/mysql
    #innodb_data_file_path = ibdata1:10M:autoextend
    #innodb_log_group_home_dir = /var/lib/mysql
    # You can set .._buffer_pool_size up to 50 - 80 %
    # of RAM but beware of setting memory usage too high
    #innodb_buffer_pool_size = 256M
    #innodb_additional_mem_pool_size = 20M
    # Example MySQL config file for large systems.
    #
    # This is for a large system with memory = 512M where the system runs mainly
    # MySQL.
    #
    # MySQL programs look for option files in a set of
    # locations which depend on the deployment platform.
    # You can copy this option file to one of those
    # locations. For information about these locations, see:
    # http://dev.mysql.com/doc/mysql/en/option-files.html
    #
    # In this file, you can use all long options that a program supports.
    # If you want to know which options a program supports, run the program
    # with the "--help" option.
    
    # The following options will be passed to all MySQL clients
    [client]
    #password       = your_password
    port            = 3306
    # This is for a large system with memory = 512M where the system runs mainly
    # MySQL.
    #
    # MySQL programs look for option files in a set of
    # locations which depend on the deployment platform.
    # You can copy this option file to one of those
    # locations. For information about these locations, see:
    # http://dev.mysql.com/doc/mysql/en/option-files.html
    #
    # In this file, you can use all long options that a program supports.
    # If you want to know which options a program supports, run the program
    # with the "--help" option.
    
    # The following options will be passed to all MySQL clients
    [client]
    default-character-set=utf8
    #password       = your_password
    port            = 3306
    socket          = /var/lib/mysql/mysql.sock
    
    # Here follows entries for some specific programs
    
    # The MySQL server
    [mysqld]
    lower_case_table_names=1
    port            = 3306
    socket          = /var/lib/mysql/mysql.sock
    skip-locking
    key_buffer_size = 256M
    max_allowed_packet = 1M
    table_open_cache = 256
    sort_buffer_size = 1M
    read_buffer_size = 1M
    read_rnd_buffer_size = 4M
    myisam_sort_buffer_size = 64M
    thread_cache_size = 8
    query_cache_size= 16M
    # Try number of CPU's*2 for thread_concurrency
    thread_concurrency = 8
    
    # Don't listen on a TCP/IP port at all. This can be a security enhancement,
    # if all processes that need to connect to mysqld run on the same host.
    # All interaction with mysqld must be made via Unix sockets or named pipes.
    # Note that using this option without enabling named pipes on Windows
    # (via the "enable-named-pipe" option) will render mysqld useless!
    #
    #skip-networking
    
    # Replication Master Server (default)
    # binary logging is required for replication
    log-bin=mysql-bin
    
    # binary logging format - mixed recommended
    binlog_format=mixed
    
    # required unique id between 1 and 2^32 - 1
    # defaults to 1 if master-host is not set
    # but will not function as a master if omitted
    server-id       = 1
    
    # Replication Slave (comment out master section to use this)
    #
    # To configure this host as a replication slave, you can choose between
    # two methods :
    #
    # 1) Use the CHANGE MASTER TO command (fully described in our manual) -
    #    the syntax is:
    #
    #    CHANGE MASTER TO MASTER_HOST=<host>, MASTER_PORT=<port>,
    #    MASTER_USER=<user>, MASTER_PASSWORD=<password> ;
    #
    #    where you replace <host>, <user>, <password> by quoted strings and
    #    <port> by the master's port number (3306 by default).
    #
    #    Example:
    #
    #    CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,
    #    MASTER_USER='joe', MASTER_PASSWORD='secret';
    #
    # OR
    #
    # 2) Set the variables below. However, in case you choose this method, then
    #    start replication for the first time (even unsuccessfully, for example
    #    if you mistyped the password in master-password and the slave fails to
    #    connect), the slave will create a master.info file, and any later
    #    change in this file to the variables' values below will be ignored and
    #    overridden by the content of the master.info file, unless you shutdown
    #    the slave server, delete master.info and restart the slaver server.
    #    For that reason, you may want to leave the lines below untouched
    #    (commented) and instead use CHANGE MASTER TO (see above)
    #
    # required unique id between 2 and 2^32 - 1
    # (and different from the master)
    # defaults to 2 if master-host is set
    # but will not function as a slave if omitted
    #server-id       = 2
    #
    # The replication master for this slave - required
    #master-host     =   <hostname>
    #
    # The username the slave will use for authentication when connecting
    # to the master - required
    #master-user     =   <username>
    #
    # The password the slave will authenticate with when connecting to
    # the master - required
    #master-password =   <password>
    #
    # The port the master is listening on.
    # optional - defaults to 3306
    #master-port     =  <port>
    #
    # binary logging - not required for slaves, but recommended
    #log-bin=mysql-bin
    
    # Uncomment the following if you are using InnoDB tables
    #innodb_data_home_dir = /var/lib/mysql
    #innodb_data_file_path = ibdata1:10M:autoextend
    #innodb_log_group_home_dir = /var/lib/mysql
    # You can set .._buffer_pool_size up to 50 - 80 %
    # of RAM but beware of setting memory usage too high
    #innodb_buffer_pool_size = 256M
    #innodb_additional_mem_pool_size = 20M
    socket          = /var/lib/mysql/mysql.sock
    
    # Here follows entries for some specific programs
    
    # The MySQL server
    [mysqld]
    lower_case_table_names=1
    port            = 3306
    socket          = /var/lib/mysql/mysql.sock
    skip-locking
    key_buffer_size = 256M
    max_allowed_packet = 1M
    table_open_cache = 256
    sort_buffer_size = 1M
    read_buffer_size = 1M
    read_rnd_buffer_size = 4M
    myisam_sort_buffer_size = 64M
    thread_cache_size = 8
    query_cache_size= 16M
    # Try number of CPU's*2 for thread_concurrency
    thread_concurrency = 8
    default-character-set=utf8
    # Don't listen on a TCP/IP port at all. This can be a security enhancement,
    "/etc/my.cnf" 148L, 4740C written                             
    [root@localhost mysql-server-5.1.73]# serv
    servertool  service   
    
    
    ----------
    [root@localhost mysql-server-5.1.73]# service mysqld restart
    ----------
    
    
    Stopping mysqld:  [  OK  ]
    Starting mysqld:  [  OK  ]
    展开全文
  • 在一切准备就绪后,启动系统,发现系统报错,怎么也找不到相应的表,按道理数据都是一样的,很纳闷,后来看日志看久了突然发现系统中存数据时候是直接用大写的表名插入,而mysqllinux下默认是严格区分大小写的,...

    由于要做mysql数据迁移,从window的数据迁移到linux,在一切准备就绪后,启动系统,发现系统报错,怎么也找不到相应的表,按道理数据都是一样的,很纳闷,后来看日志看久了突然发现系统中存数据时候是直接用大写的表名插入,而mysql在linux下默认是严格区分大小写的,因此会出现找不到表的情况,简直了。后来在网上查了些资料,才通过配置搞定了这件事,具体资料如下:


    Linux] MySQL在Linux下数据库名、表名、列名、别名大小写规则: 

       1、数据库名与表名是严格区分大小写 

       2、表的别名是严格区分大小写 

       3、列名与列的别名在所有的情况下均是忽略大小写的 

       4、变量名也是严格区分大小写的 

    改变表名的大小写区分规则的方法,修改/etc/my.cnf,在[mysqld]后添加添加lower_case_table_names=1,重启MySQL服务,若设置成功,则不再区分表名的大小写。 

     

    Windows ] MySQL在Windows下数据库名、表名、列名、别名都不区分大小写。 

    如果想大小写区分则在my.ini 里面的mysqld部分 ,加入 lower_case_table_names=0 

    注意:Windows中即使改了这个设置,在查询时还是不会区分大小写。只是在导入导出时会对大小写有区别。

     

    2、查询时where条件是否区分大小写

    ------------------------------------------------------------------

    取决于库或表上的collate(核对、对比) 属性的值。

    例如我们使用UTF8编码,collate使用utf8_bin时区分大小写,collate使用utf8_general_ci时不区分大小写

     

    建库语句:

    CREATE DATABASE mydb DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci; (不区分大小写)

     

    建表语句:

    CREATE TABLE test2(id int(10),name char(10))

    ENGINE = InnoDB

    COLLATE = 'utf8_bin'  (区分大小写)

     

    建表时指明了collate,则对对表有效。建表时未指明collate,则使用库上的collate属性。

    展开全文
  • Mysql大小写敏感问题

    千次阅读 2018-12-27 14:55:48
    Mysql大小写敏感问题 文章目录Mysql大小写敏感问题前言数据库名与表名大小写敏感?windowslinux列名大小写敏感?字段内容大小写敏感?windows方法一方法二方法三(推荐)方法四linux总结 前言 Mysql有如下三个大小写...

    Mysql大小写敏感问题

    前言

    Mysql有如下三个大小写敏感相关问题。

    1. 数据库名与表名
    2. 列名和列的别外
    3. 字段内容

    数据库名与表名大小写敏感?

    windows

    默认情况,数据库名与表名是不区分大小写

    若想修改为大小写敏感,如下配置:

    1. 打开C:\ProgramData\MySQL\MySQL Server 5.7目录,找到my.ini文件并打开。
    2. 在结尾处添加如下代码
    #区分大小写
    lower_case_table_names=2
    

    有人说如下设置lower_case_table_names=0 这样会报错。
    可参数MySQL配置文件-my.ini理解my.ini文件

    1. 重启mysql服务
    net stop MySQL57;
    net start MySQL57;
    
    1. 验证,执行sql语句
    show global variables like '%lower_case%';
    

    ps
    把lower_case_table_names从0改变为1
    在你把lower_case_table_names设置为1时,在restart你的mysqld之前,请把数据库名和表名更改为小写

    linux

    默认情况,数据库名与表名是严格区分大小写
    若想修改为大小写敏感,如下配置:

    1. 打开 /etc/my.cnf,添加如下lower_case_table_names = 1 //大小写不敏感
    2. 设置好后重启服务:systemctl restart mysqld
    3. 验证
    show variables like "%case%";
    

    列名大小写敏感?

    windows和linux默认情况,列名与列的别名在所有的情况下均是忽略大小写的;

    字段内容大小写敏感?

    这个很重要,不然会闹出笑话的。

    windows

    默认情况,字段内容大小写不敏感

    若想修改为大小写敏感,如下配置:

    方法一

    在创建表时指定字段的校验规则,使用BINARY ,比如create table aa (a varchar(20) BINARY , c varchar(20)) ;

    或者(推荐)

    DROP TABLE IF EXISTS `aa`;
    CREATE TABLE `aa` (
      `a` varchar(20) CHARACTER SET utf8 COLLATE utf8_bin DEFAULT NULL,
      `c` varchar(20) DEFAULT NULL
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    

    方法二

    表已经创建,执行修改sql语句
    alter table test3 modify name varchar(20) collate utf8_bin;,其实本质上也是把collatioin(校对)模式改成二进制校对,实现大小写敏感。

    方法三(推荐)

    使用Navicat for MySQL工具,打开设计表,选中字段,在下面的排序规则里选中utf8-bin
    在这里插入图片描述

    方法四

    不修改mysql,修改查询语句
    指定Collation:select * from case1 where B like ‘%b%’ collate utf8_bin;
    通过binary把字符串转化为二进制比较:select * from case1 where binary B like ‘%b%’;

    原理
    字段值的大小写由mysql的校对规则来控制。提到校对规则,就不得不说字符集。字符集是一套符号和编码,校对规则是在字符集内用于比较字符的一套规则 .
    一般而言,校对规则以其相关的字符集名开始,通常包括一个语言名,并且以_ci(大小写不敏感)、_cs(大小写敏感)或_bin(二元)结束 。比如 utf8字符集,utf8_general_ci,表示不区分大小写,这个是utf8字符集默认的校对规则;utf8_general_cs表示区分大小写,utf8_bin表示二进制比较,同样也区分大小写 。

    总结:只要在创建表的时候指定collate为utf8_bin,就可以实现大小写敏感,如果建表时未指定,则可修改字段的校对规则,也可以实现大小写敏感。

    linux

    默认情况,字段内容大小写不敏感
    若想修改为大小写敏感,设置方法如上windows

    总结

    windows

    1、数据库名与表名是忽略大小写;
    2、表的别名是忽略大小写;
    3、列名与列的别名是忽略大小写;
    4、字段内容默认情况下是严格区分大小写。
    

    linux

    1、数据库名与表名是严格区分大小写;
    2、表的别名是严格区分大小写;
    3、列名与列的别名是忽略大小写;
    4、字段内容是忽略大小写。
    
    展开全文
  • java 调用linux命令需要制定路径+命令。 查看命令路径命令:whereis ***** ...mysql 中当字段存储格式为:utf8_general_ci时不区分大小写,也就是同时添加A,a将会报错,应将编码该为 utf8_general_cs ,utf8_bin

    java 调用linux命令需要制定路径+命令。

    查看命令路径命令:whereis *****

    mysql 中当字段存储格式为:utf8_general_ci时不区分大小写,也就是同时添加A,a将会报错,应将编码该为 utf8_general_cs ,utf8_bin

    展开全文
  • MySQL大小写问题

    2014-03-12 18:13:11
    MySQLlinux下数据库、表名、列名、别名的规则: 1.数据库名与表名是严格区分大小写; 2.表的别名是严格区分大小写的; 3.变量名严格区分大小写; 4.列名与列的别名忽略大小写
  • MySQL大小写敏感问题

    2019-05-16 16:21:58
    后来发现windows和linux下的mysql大小写敏感是有区别的。 mysql版本:5.7 这是本次测试的例图 这是服务器测试的例图 报错信息已经提到了sql语句以及数据库的问题,我们先看一下数据库吧 本地: 服务器: 没有...
  • 又有些日子没来iteye了,今天有空,来这写写东西,近日要准备做一个.net迁移java的项目,原先的项目全是.net,编码规范和风格,浓浓的微软风格。第一个切入口,把原有的新闻模块迁移过来,数据库还是原先的不变...
  • MySQL大小写问题

    千次阅读 2010-10-05 22:22:00
    MySQL大小写问题 (本文来自:http://www.javaeye.com/topic/766135) MySQL大小写问题 不是一个很大的问题,但是如果不了解的话,却会使用户产生迷惑 ;如下面 Sql代码 insert into t values('A');...
  • Linux在线安装Mysql5.7 yum安装wget yum -y install wget
  • MYSQL 大小写区分说明

    千次阅读 2015-08-13 01:15:11
    1、linuxmysql安装完后是默认:区分表名的大小写,不区分列名的大小写; 2、用root帐号登录后,在/etc/my.cnf 或my.ini中的[mysqld]后添加添加lower_case_table_names=1,重启MYSQL服务,这时已设置成功:不...
  • 一个因MySQL大小写敏感导致的问题

    千次阅读 多人点赞 2019-06-12 23:56:47
    做一个积极的人 编码、改bug、提升自己 我有一个乐园,面向编程,春暖花开! 分享一下大神老师的人工智能教程。零基础!...文章目录00 MYSQL大小写敏感01 一个表字母大小故事lower_case_file_s...
  • 因此,所使用操作系统的大小写敏感性决定了数据库名和表名的大小写敏感性。 在大多数Unix中数据库名和表名对大小写敏感,而在Windows中对大小写不敏感。一个显著的例外情况是Mac OS X,它基于Unix但使用默认文件...
  • 好好耕耘 Mysql的表名/字段名/字段值是否区分大小写 1、MySQL默认情况下是否区分大小写...2、mysql对于类型为varchar数据默认不区分大小写,但如果该字段以“*_bin”编码的话会使mysql对其区分大小写。 3、mysql对...
  • 前段时间,因为要用到mysql做个东西,但是却总是遇到乱码问题,网上给除了解决办法,但是,在我的电脑上老是行不通。虽然怀疑或是版本的问题,但是,却苦于不知道该怎么解决。今天无意中从linux公社中看到这篇文章,...
  • MySQL数据库大小写敏感设置

    千次阅读 2020-03-10 09:50:42
    MySQLlinux服务器的/etc/my.cnf目录下,安装的时候默认设置参数是大小写敏感的: lower_case_table_names = 0 大小写敏感 lower_case_table_names = 1 大小写不敏感 设置好后重启服务: service mysqld stop ...
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