centos7使用yum提示有未完成的事务

There are unfinished transactions remaining. You might consider running yum-complete-transaction, or "yum-complete-transaction --cleanup-only" and "yum history redo last", first to finish them. If those don't work you'll have to try removing/installing packages by hand (maybe package-cleanup can help).
The program yum-complete-transaction is found in the yum-utils package.

使用yum安装软件包的时候，强制退出yum或者yum异常退出造成的，再次使用yum时就会提示上述的错误：
解决：

1、安装yum-complete-transaction，这个工具是在yum-utils这个包里面，所以，需要先安装yum-utils才能使用yum-complete-transaction

# yum -y install yum-utils

2、清理缓存

# yum clean all

3、执行清理未完成事物

# yum-complete-transaction --cleanup-only

 

另：

Transaction check error:
  package zlib-1.2.7-19.el7_9.x86_64 is already installed

错误概要

出现Transaction check error，软件包冲突，卸载掉这个软件包重新安装即可

# yum -y remove zlib-1.2.7-19.el7_9.x86_64