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配置mysql yum源

[root@iZbp1j6oiamq7t2otpryarZ ~]# cd /data/
[root@iZbp1j6oiamq7t2otpryarZ data]# ll
total 0###################################下载mysql源安装包#
[root@iZbp1j6oiamq7t2otpryarZ data]# wget -P ./ http://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm
--2017-11-02 13:04:56--  http://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm
Resolving dev.mysql.com (dev.mysql.com)... 137.254.60.11
Connecting to dev.mysql.com (dev.mysql.com)|137.254.60.11|:80... connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: https://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm [following]
--2017-11-02 13:04:57--  https://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm
Connecting to dev.mysql.com (dev.mysql.com)|137.254.60.11|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://repo.mysql.com//mysql57-community-release-el7-8.noarch.rpm [following]
--2017-11-02 13:04:59--  https://repo.mysql.com//mysql57-community-release-el7-8.noarch.rpm
Resolving repo.mysql.com (repo.mysql.com)... 118.215.180.109
Connecting to repo.mysql.com (repo.mysql.com)|118.215.180.109|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 9116 (8.9K) [application/x-redhat-package-manager]
Saving to: ‘./mysql57-community-release-el7-8.noarch.rpm’100%[===================================================================================================>] 9,116       --.-K/s   in 0s      2017-11-02 13:04:59 (145 MB/s) - ‘./mysql57-community-release-el7-8.noarch.rpm’ saved [9116/9116][root@iZbp1j6oiamq7t2otpryarZ data]# ll
total 12
-rw-r--r-- 1 root root 9116 Apr 11  2016 mysql57-community-release-el7-8.noarch.rpm####################################安装mysql源#
[root@iZbp1j6oiamq7t2otpryarZ data]# yum localinstall mysql57-community-release-el7-8.noarch.rpm
Loaded plugins: fastestmirror
Examining mysql57-community-release-el7-8.noarch.rpm: mysql57-community-release-el7-8.noarch
Marking mysql57-community-release-el7-8.noarch.rpm to be installed
Resolving Dependencies
--> Running transaction check
---> Package mysql57-community-release.noarch 0:el7-8 will be installed
--> Finished Dependency ResolutionDependencies Resolved=============================================================================================================================================Package                                Arch                Version               Repository                                            Size
=============================================================================================================================================
Installing:mysql57-community-release              noarch              el7-8                 /mysql57-community-release-el7-8.noarch              8.2 kTransaction Summary
=============================================================================================================================================
Install  1 PackageTotal size: 8.2 k
Installed size: 8.2 k
Is this ok [y/d/N]: y
Downloading packages:
Running transaction check
Running transaction test
Transaction test succeeded
Running transactionInstalling : mysql57-community-release-el7-8.noarch                                                                                    1/1 Verifying  : mysql57-community-release-el7-8.noarch                                                                                    1/1 Installed:mysql57-community-release.noarch 0:el7-8                                                                                                   Complete!####################################检查mysql源是否安装成功#
[root@iZbp1j6oiamq7t2otpryarZ data]# yum repolist enabled | grep "mysql.*-community.*"
mysql-connectors-community/x86_64 MySQL Connectors Community                  42
mysql-tools-community/x86_64      MySQL Tools Community                       51
mysql57-community/x86_64          MySQL 5.7 Community Server                 227
###########看到上面内容，表示安装成功。####################################
# mysql源配置文件：/etc/yum.repos.d/mysql-community.repo
# 比如要安装5.6版本，可将5.7源的enabled=1改成enabled=0。并将5.6源的enabled=0改成enabled=1即可。
####################################
[root@iZbp1j6oiamq7t2otpryarZ data]# cat /etc/yum.repos.d/mysql-community.repo
[mysql-connectors-community]
name=MySQL Connectors Community
baseurl=http://repo.mysql.com/yum/mysql-connectors-community/el/7/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql[mysql-tools-community]
name=MySQL Tools Community
baseurl=http://repo.mysql.com/yum/mysql-tools-community/el/7/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql# Enable to use MySQL 5.5
[mysql55-community]
name=MySQL 5.5 Community Server
baseurl=http://repo.mysql.com/yum/mysql-5.5-community/el/7/$basearch/
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql# Enable to use MySQL 5.6
[mysql56-community]
name=MySQL 5.6 Community Server
baseurl=http://repo.mysql.com/yum/mysql-5.6-community/el/7/$basearch/
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql[mysql57-community]
name=MySQL 5.7 Community Server
baseurl=http://repo.mysql.com/yum/mysql-5.7-community/el/7/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql[mysql-tools-preview]
name=MySQL Tools Preview
baseurl=http://repo.mysql.com/yum/mysql-tools-preview/el/7/$basearch/
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql[root@iZbp1j6oiamq7t2otpryarZ data]#

安装mysql：

#################################### 安装MySQL #
[root@iZbp1j6oiamq7t2otpryarZ data]# yum install mysql-community-server
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
Resolving Dependencies
--> Running transaction check
---> Package mysql-community-server.x86_64 0:5.7.20-1.el7 will be installed
--> Processing Dependency: mysql-community-common(x86-64) = 5.7.20-1.el7 for package: mysql-community-server-5.7.20-1.el7.x86_64
--> Processing Dependency: mysql-community-client(x86-64) >= 5.7.9 for package: mysql-community-server-5.7.20-1.el7.x86_64
--> Processing Dependency: libaio.so.1(LIBAIO_0.4)(64bit) for package: mysql-community-server-5.7.20-1.el7.x86_64
--> Processing Dependency: libaio.so.1(LIBAIO_0.1)(64bit) for package: mysql-community-server-5.7.20-1.el7.x86_64
--> Processing Dependency: libaio.so.1()(64bit) for package: mysql-community-server-5.7.20-1.el7.x86_64
--> Running transaction check
---> Package libaio.x86_64 0:0.3.109-13.el7 will be installed
---> Package mysql-community-client.x86_64 0:5.7.20-1.el7 will be installed
--> Processing Dependency: mysql-community-libs(x86-64) >= 5.7.9 for package: mysql-community-client-5.7.20-1.el7.x86_64
---> Package mysql-community-common.x86_64 0:5.7.20-1.el7 will be installed
--> Running transaction check
---> Package mariadb-libs.x86_64 1:5.5.52-1.el7 will be obsoleted
--> Processing Dependency: libmysqlclient.so.18()(64bit) for package: 2:postfix-2.10.1-6.el7.x86_64
--> Processing Dependency: libmysqlclient.so.18(libmysqlclient_18)(64bit) for package: 2:postfix-2.10.1-6.el7.x86_64
---> Package mysql-community-libs.x86_64 0:5.7.20-1.el7 will be obsoleting
--> Running transaction check
---> Package mysql-community-libs-compat.x86_64 0:5.7.20-1.el7 will be obsoleting
--> Finished Dependency ResolutionDependencies Resolved=============================================================================================================================================Package                                     Arch                   Version                          Repository                         Size
=============================================================================================================================================
Installing:mysql-community-libs                        x86_64                 5.7.20-1.el7                     mysql57-community                 2.1 Mreplacing  mariadb-libs.x86_64 1:5.5.52-1.el7mysql-community-libs-compat                 x86_64                 5.7.20-1.el7                     mysql57-community                 2.0 Mreplacing  mariadb-libs.x86_64 1:5.5.52-1.el7mysql-community-server                      x86_64                 5.7.20-1.el7                     mysql57-community                 164 M
Installing for dependencies:libaio                                      x86_64                 0.3.109-13.el7                   base                               24 kmysql-community-client                      x86_64                 5.7.20-1.el7                     mysql57-community                  24 Mmysql-community-common                      x86_64                 5.7.20-1.el7                     mysql57-community                 272 kTransaction Summary
=============================================================================================================================================
Install  3 Packages (+3 Dependent packages)Total download size: 192 M
Is this ok [y/d/N]: y
Downloading packages:
(1/6): libaio-0.3.109-13.el7.x86_64.rpm                                                                               |  24 kB  00:00:00     
warning: /var/cache/yum/x86_64/7/mysql57-community/packages/mysql-community-common-5.7.20-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Public key for mysql-community-common-5.7.20-1.el7.x86_64.rpm is not installed
(2/6): mysql-community-common-5.7.20-1.el7.x86_64.rpm                                                                 | 272 kB  00:00:00     
(3/6): mysql-community-libs-5.7.20-1.el7.x86_64.rpm                                                                   | 2.1 MB  00:00:00     
(4/6): mysql-community-libs-compat-5.7.20-1.el7.x86_64.rpm                                                            | 2.0 MB  00:00:00     
(5/6): mysql-community-client-5.7.20-1.el7.x86_64.rpm                                                                 |  24 MB  00:00:08     
(6/6): mysql-community-server-5.7.20-1.el7.x86_64.rpm                                                                 | 164 MB  00:01:10     
---------------------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                        2.6 MB/s | 192 MB  00:01:13     
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql
Importing GPG key 0x5072E1F5:Userid     : "MySQL Release Engineering <mysql-build@oss.oracle.com>"Fingerprint: a4a9 4068 76fc bd3c 4567 70c8 8c71 8d3b 5072 e1f5Package    : mysql57-community-release-el7-8.noarch (installed)From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-mysql
Is this ok [y/N]: y
Running transaction check
Running transaction test
Transaction test succeeded
Running transactionInstalling : mysql-community-common-5.7.20-1.el7.x86_64                                                                                1/7 Installing : mysql-community-libs-5.7.20-1.el7.x86_64                                                                                  2/7 Installing : mysql-community-client-5.7.20-1.el7.x86_64                                                                                3/7 Installing : libaio-0.3.109-13.el7.x86_64                                                                                              4/7 Installing : mysql-community-server-5.7.20-1.el7.x86_64                                                                                5/7 Installing : mysql-community-libs-compat-5.7.20-1.el7.x86_64                                                                           6/7 Erasing    : 1:mariadb-libs-5.5.52-1.el7.x86_64                                                                                        7/7 Verifying  : mysql-community-libs-5.7.20-1.el7.x86_64                                                                                  1/7 Verifying  : mysql-community-server-5.7.20-1.el7.x86_64                                                                                2/7 Verifying  : mysql-community-common-5.7.20-1.el7.x86_64                                                                                3/7 Verifying  : mysql-community-client-5.7.20-1.el7.x86_64                                                                                4/7 Verifying  : mysql-community-libs-compat-5.7.20-1.el7.x86_64                                                                           5/7 Verifying  : libaio-0.3.109-13.el7.x86_64                                                                                              6/7 Verifying  : 1:mariadb-libs-5.5.52-1.el7.x86_64                                                                                        7/7 Installed:mysql-community-libs.x86_64 0:5.7.20-1.el7 mysql-community-libs-compat.x86_64 0:5.7.20-1.el7 mysql-community-server.x86_64 0:5.7.20-1.el7Dependency Installed:libaio.x86_64 0:0.3.109-13.el7       mysql-community-client.x86_64 0:5.7.20-1.el7       mysql-community-common.x86_64 0:5.7.20-1.el7      Replaced:mariadb-libs.x86_64 1:5.5.52-1.el7                                                                                                         Complete!

启动mysql服务

[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl start mysqld
[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl status mysqld
● mysqld.service - MySQL ServerLoaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)Active: active (running) since Thu 2017-11-02 13:23:48 CST; 18s agoDocs: man:mysqld(8)http://dev.mysql.com/doc/refman/en/using-systemd.htmlProcess: 23892 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)Process: 23818 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)Main PID: 23895 (mysqld)CGroup: /system.slice/mysqld.service└─23895 /usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pidNov 02 13:23:42 iZbp1j6oiamq7t2otpryarZ systemd[1]: Starting MySQL Server...
Nov 02 13:23:48 iZbp1j6oiamq7t2otpryarZ systemd[1]: Started MySQL Server.

开机启动

[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl enable mysqld
[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl daemon-reload

停止mysql服务

[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl stop mysqld
[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl status mysqld
● mysqld.service - MySQL ServerLoaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)Active: inactive (dead) since Thu 2017-11-02 13:31:35 CST; 5s agoDocs: man:mysqld(8)http://dev.mysql.com/doc/refman/en/using-systemd.htmlMain PID: 23895 (code=exited, status=0/SUCCESS)Nov 02 13:23:42 iZbp1j6oiamq7t2otpryarZ systemd[1]: Starting MySQL Server...
Nov 02 13:23:48 iZbp1j6oiamq7t2otpryarZ systemd[1]: Started MySQL Server.
Nov 02 13:31:33 iZbp1j6oiamq7t2otpryarZ systemd[1]: Stopping MySQL Server...
Nov 02 13:31:35 iZbp1j6oiamq7t2otpryarZ systemd[1]: Stopped MySQL Server.
[root@iZbp1j6oiamq7t2otpryarZ data]#

更改数据文件位置：

将/var/lib下的mysql目录，mv（移动）到/data目录下：

为什么要用mv命令，而不用cp命令呢？应为linux文件系统特殊性，mv命令能保留文件的所有属性和权限，尤其是selinux属性。如果用cp命令，就需要回头再去设置mysql文件夹的selinux属性，本人因很头疼selinux故能避则避。

[root@iZbp1j6oiamq7t2otpryarZ data]# mv /var/lib/mysql /data/mysql
[root@iZbp1j6oiamq7t2otpryarZ data]# ll
total 12
drwxr-x--x 5 mysql mysql  314 Nov  2 13:31 mysql
-rw-r--r-- 1 root  root  9116 Apr 11  2016 mysql57-community-release-el7-8.noarch.rpm
[root@iZbp1j6oiamq7t2otpryarZ data]#

修改mysql配置文件/etc/my.cnf。将datadir和socket的路径改为/data目录下：

[root@iZbp1j6oiamq7t2otpryarZ data]# cat /etc/my.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
[root@iZbp1j6oiamq7t2otpryarZ data]# vi /etc/my.cnf
[root@iZbp1j6oiamq7t2otpryarZ data]# cat /etc/my.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/data/mysql
socket=/data/mysql/mysql.sock[mysqld_safe]
socket=/data/mysql/mysql.sock
[client]
socket=/data/mysql/mysql.sock
[mysql.server]
socket=/data/mysql/mysql.sock# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid[root@iZbp1j6oiamq7t2otpryarZ data]#

然后重新启动mysql服务：

[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl restart mysqld
[root@iZbp1j6oiamq7t2otpryarZ data]# systemctl status mysqld
● mysqld.service - MySQL ServerLoaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)Active: active (running) since Thu 2017-11-02 13:40:54 CST; 5s agoDocs: man:mysqld(8)http://dev.mysql.com/doc/refman/en/using-systemd.htmlProcess: 24037 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)Process: 24019 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)Main PID: 24040 (mysqld)CGroup: /system.slice/mysqld.service└─24040 /usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pidNov 02 13:40:53 iZbp1j6oiamq7t2otpryarZ systemd[1]: Starting MySQL Server...
Nov 02 13:40:54 iZbp1j6oiamq7t2otpryarZ systemd[1]: Started MySQL Server.
[root@iZbp1j6oiamq7t2otpryarZ data]#

修改root本地登录密码

mysql安装完成之后，在/var/log/mysqld.log文件中给root生成了一个默认密码。通过下面的方式找到root默认密码，然后登录mysql进行修改：

[root@iZbp1j6oiamq7t2otpryarZ data]# grep 'temporary password' /var/log/mysqld.log
2017-11-02T05:23:44.524190Z 1 [Note] A temporary password is generated for root@localhost: MyOldPass123!
[root@iZbp1j6oiamq7t2otpryarZ data]#

[root@iZbp1j6oiamq7t2otpryarZ data]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.20Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql>  
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass123!';

或者

mysql> set password for 'root'@'localhost'=password('MyNewPass123!');

注意：
mysql5.7默认安装了密码安全检查插件（validate_password），默认密码检查策略要求密码必须包含：大小写字母、数字和特殊符号，并且长度不能少于8位，否则会提示：
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'gq123!mysql';
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

通过msyql环境变量可以查看密码策略的相关信息：

mysql> show variables like '%password%';
+---------------------------------------+--------+
| Variable_name                         | Value  |
+---------------------------------------+--------+
| default_password_lifetime             | 0      |
| disconnect_on_expired_password        | ON     |
| log_builtin_as_identified_by_password | OFF    |
| mysql_native_password_proxy_users     | OFF    |
| old_passwords                         | 0      |
| report_password                       |        |
| sha256_password_proxy_users           | OFF    |
| validate_password_check_user_name     | OFF    |
| validate_password_dictionary_file     |        |
| validate_password_length              | 8      |
| validate_password_mixed_case_count    | 1      |
| validate_password_number_count        | 1      |
| validate_password_policy              | MEDIUM |
| validate_password_special_char_count  | 1      |
+---------------------------------------+--------+
14 rows in set (0.00 sec)mysql>

validate_password_policy：密码策略，默认为MEDIUM策略
validate_password_dictionary_file：密码策略文件，策略为STRONG才需要
validate_password_length：密码最少长度
validate_password_mixed_case_count：大小写字符长度，至少1个
validate_password_number_count ：数字至少1个
validate_password_special_char_count：特殊字符至少1个
上述参数是默认策略MEDIUM的密码检查规则。

共有以下几种密码策略：

策略	检查规则
0 or LOW	Length
1 or MEDIUM	Length; numeric, lowercase/uppercase, and special characters
2 or STRONG	Length; numeric, lowercase/uppercase, and special characters; dictionary file

MySQL官网密码策略详细说明：
http://dev.mysql.com/doc/refman/5.7/en/validate-password-options-variables.html#sysvar_validate_password_policy

修改密码策略

在/etc/my.cnf文件添加validate_password_policy配置，指定密码策略

# 选择0（LOW），1（MEDIUM），2（STRONG）其中一种，选择2需要提供密码字典文件
validate_password_policy=0

如果不需要密码策略，添加my.cnf文件中添加如下配置禁用即可：

validate_password = off

重新启动mysql服务使配置生效：

systemctl restart mysqld

添加远程登录用户

默认只允许root帐户在本地登录，如果要在其它机器上连接mysql，必须修改root允许远程连接，或者添加一个允许远程连接的帐户，为了安全起见，我添加一个新的帐户：

mysql> GRANT ALL PRIVILEGES ON *.* TO 'yuanchengyonghu'@'%' IDENTIFIED BY 'MyNewPass123' WITH GRANT OPTION;

配置默认编码为utf8

修改/etc/my.cnf配置文件，在[mysqld]下添加编码配置，如下所示：

#在[mysqld]下添加如下内容#
character_set_server=utf8
init_connect='SET NAMES utf8'

设置mysql大小不敏感

lower_case_table_names=1

设置最大连接数及超时时间

max_connections=1000
#max_user_connections=500
wait_timeout=2880

重新启动mysql服务，查看数据库默认编码如下：

[root@iZbp1j6oiamq7t2otpryarZ data]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.20 MySQL Community Server (GPL)Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql> show variables like '%character%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
8 rows in set (0.01 sec)mysql>