MySQL simple knowledge
----------------------------------------------- -------------------------------------------------- -------------
A, mysql is the C / S model structure, namely: client (Client) + server (server)
Second, how the application connects to mysql:
1, TCP / IP connected database
mysql -uadmin -p123 -h 10.0.0.51 -P 3306
It can be shown that:
(1) database was good
(2) the network connection is no problem in
(3) the user is no problem
2, SOCKET connect database
mysql -uroot -p123456 -S /application/mysql/tmp/mysql.sock
Thoughts:
MySQL-uroot--p123456 What is the use to log ?????
In fact, the database connection used SOCKET way, but here is the default -S hidden.
Careful you must find a compiler installed in front of us, the compiler parameter which specifies the file sockt
Path /application/mysql-5.6.34/tmp/mysql.sock, because the compiler specified socket, so here is compiled using the default path.
Third, the multi-instance install mysql
That is, a server above, start multiple mysql, each run independently.
Planning:
1, start times the mysqld_safe
2, respectively, by preparing a plurality of my.cnf = File---defaults the mysqld_safe
. 3, a plurality of ports 3307, 3308,3309
4, initialization data sets
5, each socket is defined in the configuration file , log_error, datadir, server_id, port
Configure multiple instances:
Create the necessary directory
[root @ mysql181 ~] # mkdir -p /data/330{7..9}/data
创建配置文件：
[root@mysql181 ~]# cat /data/3307/my.cnf /data/3308/my.cnf /data/3309/my.cnf
[mysqld]
basedir=/application/mysql
datadir=/data/3307/data
socket=/data/3307/mysql.sock
server_id=3307
port=3307
log_error=/data/3307/mysql.log
log_bin=/data/3307/mysql-bin
binlog_format=row
[client]
socket=/data/3307/mysql.sock
[mysqld]
basedir=/application/mysql
datadir=/data/3308/data
socket=/data/3308/mysql.sock
server_id=3308
port=3308
log_error=/data/3308/mysql.log
log_bin=/data/3308/mysql-bin
binlog_format=row
[client]
socket=/data/3308/mysql.sock
[mysqld]
basedir=/application/mysql
datadir=/data/3309/data
socket=/data/3309/mysql.sock
server_id=3309
port=3309
log_error=/data/3309/mysql.log
log_bin=/data/3309/mysql-bin
binlog_format=row
[client]
socket=/data/3309/mysql.sock
[root@db01 data]#
Initialization data:
[root@mysql181 ~]# /application/mysql/scripts/mysql_install_db --user=mysql --basedir=/application/mysql --datadir=/data/3307/data/
[root@mysql181 ~]# /application/mysql/scripts/mysql_install_db --user=mysql --basedir=/application/mysql --datadir=/data/3308/data/
[root@mysql181 ~]# /application/mysql/scripts/mysql_install_db --user=mysql --basedir=/application/mysql --datadir=/data/3309/data/
Modify directory permissions
[the root @ DB01 3307] Touch # /data/330{7..9}/mysql.log
[the root @ DB01 3307] # chown -R & lt mysql.mysql / Data / 330. *
Start multi-instance
[root@mysql181 ~]# mysqld_safe --defaults-file=/data/3307/my.cnf &
[root@mysql181 ~]# mysqld_safe --defaults-file=/data/3308/my.cnf &
[root@mysql181 ~]# mysqld_safe --defaults-file=/data/3309/my.cnf &
Check whether the port to start:
Were landed 3307-3309:
[root@mysql181 ~]# mysql -S /data/3307/mysql.sock
You should connect to the database using a socket ways: Specify the file location sock
Close the database method:
[root@mysql181 ~]# mysqladmin -S /data/3307/mysql.sock shutdown
Because we do not have multi-instance startup script, in fact, we can turn on and off these two orders, write a startup script.
This multi-instance install mysql success!