如何创建一个mysql实例

mysql与ORACLE不同，没有多bai个实例这种说法。

MYSQL服务进程可以同时du服务多个DATABASE，而zhi不象ORACLE，一个实例对应一dao个DATABASE。

你的意思是再启动一个MYSQL进程吗？这也是可以的，在启动命令行中修改参数。也可以在启动配置文件my.cnf中修改。

配置文件还是一个，只不过mysql的数据库存放目录需要多个，这根据你的实例来配置数据库存放目录。

给个多实例配置案例：

初始化数据库

[mysql@localhost ~]$ mkdir /mydata/mysql_db/data_1001 #创建数据库存放目录

[mysql@localhost ~]$ mkdir /mydata/mysql_db/data_1002

[mysql@localhost ~]$ mkdir /mydata/mysql_db/data_1003

[mysql@localhost mysql_db]$ ./bin/mysql_install_db –basedir=/mydata/mysql_db –datadir=/mydata/mysql_db/data_1001 –user=mysql #数据库初始化

Installing MySQL system tables…

OK

Filling help tables…

OK

To start mysqld at boot time you have to copy

support-files/mysql.server to the right place for your system

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !

To do so, start the server, then issue the following commands:

/mydata/mysql_db/bin/mysqladmin -u root password ‘new-password’

/mydata/mysql_db/bin/mysqladmin -u root -h localhost password ‘new-password’

Alternatively you can run:

/mydata/mysql_db/bin/mysql_secure_installation

which will also give you the option of removing the test

databases and anonymous user created by default. This is

strongly recommended for production servers.

See the manual for more instructions.

You can start the MySQL daemon with:

cd /mydata/mysql_db /mydata/mysql_db/bin/mysqld_safe &

You can test the MySQL daemon with mysql-test-run.pl

cd /mydata/mysql_db/mysql-test perl mysql-test-run.pl

Please report any problems with the /mydata/mysql_db/scripts/mysqlbug script!

[mysql@localhost mysql_db]$ ./bin/mysql_install_db –basedir=/mydata/mysql_db –datadir=/mydata/mysql_db/data_1002 –user=mysql

[mysql@localhost mysql_db]$ ./bin/mysql_install_db –basedir=/mydata/mysql_db –datadir=/mydata/mysql_db/data_1003 –user=mysql

配置mysql_multi

[mysql@localhost mysql_db]$ cd /home/mysql/

[mysql@localhost ~]$ vi my.cnf

[mysqld_multi] #添加内容如下

mysqld = /mydata/mysql_db/bin/mysqld_safe

mysqladmin = /mydata/mysql_db/bin/mysqladmin

user = mysql

[mysqld1001]

port = 3306

socket = /tmp/mysql3306.sock

pid-file = /tmp/mysql3306.pid

basedir = /mydata/mysql_db

datadir = /mydata/mysql_db/data_1001

skip-locking

key_buffer_size = 16K

max_allowed_packet = 1M

table_open_cache = 4

sort_buffer_size = 64K

read_buffer_size = 256K

read_rnd_buffer_size = 256K

net_buffer_length = 2K

thread_stack = 128K

server-id = 1

[mysqld1002]

port = 3307

socket = /tmp/mysql3307.sock

basedir = /mydata/mysql_db

datadir = /mydata/mysql_db/data_1002

pid-file = /tmp/mysql3307.pid

skip-locking

key_buffer_size = 16K

max_allowed_packet = 1M

table_open_cache = 4

sort_buffer_size = 64K

read_buffer_size = 256K

read_rnd_buffer_size = 256K

net_buffer_length = 2K

thread_stack = 128K

server-id = 1

[mysqld1003]

port = 3308

socket = /tmp/mysql3308.sock

basedir = /mydata/mysql_db

datadir = /mydata/mysql_db/data_1003

pid-file = /tmp/mysql3308.pid

skip-locking

key_buffer_size = 16K

max_allowed_packet = 1M

table_open_cache = 4

sort_buffer_size = 64K

read_buffer_size = 256K

read_rnd_buffer_size = 256K

net_buffer_length = 2K

thread_stack = 128K

server-id = 1

[client]

#password = your_password

port = 3306

socket = /tmp/mysql.sock

多实例启动

[mysql@localhost mysql_db]$ mysqld_multi –defaults-file=/home/mysql/my.cnf –user=mysql start 1001-1003 #启动mysql实例

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