CentOS Package Management related finishing

First, the viewing system has been installed to the software:

1, yum list installed (+ software name)

2, RPM-QA (can cooperate with grep to see if a software is installed)

2 is much faster because it is based on a local database.
Yum also has the advantage of its very good beef B:
For example: Yum list extras
If you think that one of the RPM packages in the software store is a bit old and you install it on your own RPM package, you will find that the query feature lists the packages you have "manually" installed.
And recent parameters are also very interesting.

........

Come here first today ~