问题描述：
安装mysql 5.7 的似乎和遇到问题 mariadb-libs is obsoleted by mysql-community-libs
此问题是centos中包含又类似的依赖库 需要进行删除 后重新安装
[root@ebs-139266 home]# rpm -ivh mysql-community-*.rpm
warning: mysql-community-client-5.7.42-1.el7.x86_64.rpm: Header V4 RSA/SHA256 Signature, key ID 3a79bd29: NOKEY
error: Failed dependencies:
mariadb-libs is obsoleted by mysql-community-libs-5.7.42-1.el7.x86_64
mariadb-libs is obsoleted by mysql-community-libs-compat-5.7.42-1.el7.x86_64
perl(JSON) is needed by mysql-community-test-5.7.42-1.el7.x86_64
[root@ebs-139266 home]# yum remove mariadb-libs
Loaded plugins: fastestmirror
Resolving Dependencies
--> Running transaction check
---> Package mariadb-libs.x86_64 1:5.5.68-1.el7 will be erased
--> Processing Dependency: libmysqlclient.so.18()(64bit) for package: 2:postfix-2.10.1-9.el7.x86_64
--> Processing Dependency: libmysqlclient.so.18(libmysqlclient_18)(64bit) for package: 2:postfix-2.10.1-9.el7.x86_64
--> Running transaction check
---> Package postfix.x86_64 2:2.10.1-9.el7 will be erased
--> Finished Dependency Resolution
Dependencies Resolved
==============================================================================================================================================================================================================================================================================
Package Arch Version Repository Size
==============================================================================================================================================================================================================================================================================
Removing:
mariadb-libs x86_64 1:5.5.68-1.el7 @base 4.4 M
Removing for dependencies:
postfix x86_64 2:2.10.1-9.el7 @base 12 M
Transaction Summary
==============================================================================================================================================================================================================================================================================
Remove 1 Package (+1 Dependent package)
Installed size: 17 M
Is this ok [y/N]: y
Downloading packages:
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Erasing : 2:postfix-2.10.1-9.el7.x86_64 1/2
Erasing : 1:mariadb-libs-5.5.68-1.el7.x86_64 2/2
Verifying : 1:mariadb-libs-5.5.68-1.el7.x86_64 1/2
Verifying : 2:postfix-2.10.1-9.el7.x86_64 2/2
Removed:
mariadb-libs.x86_64 1:5.5.68-1.el7
Dependency Removed:
postfix.x86_64 2:2.10.1-9.el7
Complete!
解决办法：
卸载原来的 yum remove mariadb-libs 重新安装