centos7下安装mysql，并通过navicat远程连接mysql数据库

安装步骤:

一般网上的按照步骤都是：

#yum install mysql
#yum install mysql-server
#yum install mysql-devel

安装mysql和mysql-devel都会成功，但是mysql-server安装会根据centos7的版本而不同。

我分别用centos7 linux release 7.4和7.6安装。7.4安装不成功，7.6版本就通过了。7.4按照提示以下结果：

CentOS 7 有些版本将MySQL数据库软件从默认的程序列表中移除，用mariadb代替了。 

方法1：

网上说可以直接安装mariadb。MariaDB数据库管理系统是MySQL的一个分支，主要由开源社区在维护，采用GPL授权许可。开发这个分支的原因之一是：甲骨文公司收购了MySQL后，有将MySQL闭源的潜在风险，因此社区采用分支的方式来避开这个风险。MariaDB的目的是完全兼容MySQL，包括API和命令行，使之能轻松成为MySQL的代替品。

#yum install mariadb-server mariadb 

然后启动mariadb：

#systemctl start mariadb.service

然后正常使用mysql：

上面显示的是MariaDB，可能看起来不习惯，但是和mysql一样的操作。

方法2：

官网下载mysql:

# wget http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm
# rpm -ivh mysql-community-release-el7-5.noarch.rpm
# yum install mysql-community-server

 安装成功后，就启动mysql服务：

# systemctl start mysql.service

第一次安装的mysql，root账户没有密码的，需要设置密码：

[root@localhost home]# mysql -u root
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.6.44 MySQL Community Server (GPL)

Copyright (c) 2000, 2019, 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> 

网上说可以使用如下命令设置密码：

mysql> set password for 'root'@'localhost' =password('123456');
ERROR 1558 (HY000): Column count of mysql.user is wrong. Expected 43, found 42. Created with MySQL 50560, now running 50644. Please use mysql_upgrade to fix this error.
mysql> 

但是我的报错，是因为我升级了库，我先安装了mariaDB,然后又安装mysql替换掉了,所以执行以下命令升级,但是又引发出一个错误：

[root@localhost home]# mysql_upgrade -u root -p 13456
Enter password: 
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
Error: Failed while fetching Server version! Could be due to unauthorized access.
FATAL ERROR: Upgrade failed

看网上帖子说修改my.cnf：

在[mysqld]后面任意一行添加“skip-grant-tables”用来跳过密码验证的过程，如下图所示：

[mysqld]
  5 #
  6 # Remove leading # and set to the amount of RAM for the most important data
  7 # cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
  8 # innodb_buffer_pool_size = 128M
  9 #
 10 # Remove leading # to turn on a very important data integrity option: logging
 11 # changes to the binary log between backups.
 12 # log_bin
 13 #
 14 # Remove leading # to set options mainly useful for reporting servers.
 15 # The server defaults are faster for transactions and fast SELECTs.
 16 # Adjust sizes as needed, experiment to find the optimal values.
 17 # join_buffer_size = 128M
 18 # sort_buffer_size = 2M
 19 # read_rnd_buffer_size = 2M
 20 datadir=/var/lib/mysql
 21 socket=/var/lib/mysql/mysql.sock
 22 skip-grant-tables

然后重启mysql：

[root@localhost home]# systemctl restart mysql.service 

就可以更新mysql数据库了：

[root@localhost home]# mysql_upgrade -uroot -p123456
Warning: Using a password on the command line interface can be insecure.
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
Running 'mysqlcheck with default connection arguments
Warning: Using a password on the command line interface can be insecure.
Running 'mysqlcheck with default connection arguments
Warning: Using a password on the command line interface can be insecure.
mysql.columns_priv                                 OK
mysql.db                                           OK
mysql.event                                        OK
mysql.func                                         OK
mysql.general_log                                  OK
mysql.help_category                                OK
mysql.help_keyword                                 OK
mysql.help_relation                                OK
mysql.help_topic                                   OK
mysql.host                                         OK
mysql.ndb_binlog_index                             OK
mysql.plugin                                       OK
mysql.proc                                         OK
mysql.procs_priv                                   OK
mysql.proxies_priv                                 OK
mysql.servers                                      OK
mysql.slow_log                                     OK
mysql.tables_priv                                  OK
mysql.time_zone                                    OK
mysql.time_zone_leap_second                        OK
mysql.time_zone_name                               OK
mysql.time_zone_transition                         OK
mysql.time_zone_transition_type                    OK
mysql.user                                         OK
Running 'mysql_fix_privilege_tables'...
Warning: Using a password on the command line interface can be insecure.
Running 'mysqlcheck with default connection arguments
Warning: Using a password on the command line interface can be insecure.
mysqlcheck: Got error: 1045: Access denied for user 'root'@'localhost' (using password: YES) when trying to connect
FATAL ERROR: Error during call to mysql_check for fixing the db/tables names on all db(s) except mysql
您在 /var/spool/mail/root 中有邮件

绕了一大圈回来，再重置mysql账号密码，下面的root就是你的用户名，123456就是密码：

mysql> set password for 'root'@'localhost' =password('123456');
Query OK, 0 rows affected (0.00 sec)

 

远程连接设置：

把在所有数据库的所有表的所有权限赋值给位于所有IP地址的root用户。

mysql> grant all privileges on *.* to root@'%'identified by '123456';
Query OK, 0 rows affected (0.00 sec)

如果是新用户而不是root，则要先新建用户。

mysql>create user 'username'@'%' identified by 'password';

网上可以有下载navicat破解版：https://pan.baidu.com/s/1OfFPvqrTqbUAC_Eqq2i0KA 提取密码:jgep

安装包的内容有，1.先点击navicat_trial...exe安装。

2.然后点击PatchNavicat.exe，然后选择刚刚安装的Navicat安装路径下找到navicat.exe文件，点击选择即可激活 成功。 

然后打开navicat，设置连接属性：

点击链接测试，连接成功就行了。还有点就是主要centos7的防火墙，你可以通过添加3306端口到防火墙内，让其不屏蔽3306端口，或者直接关掉防火墙就行。 

 

参考文档：https://www.cnblogs.com/starof/p/4680083.html