1.查看已装包
rpm -qa | grep pgpool
2.卸载包
rpm -e 包名
3.示例（卸载pgpool）
[root@VM_145_153_centos etc]# rpm -qa | grep pgpool
pgpool-II-pg95-debuginfo-3.7.5-1pgdg.rhel7.x86_64
pgpool-II-pg95-extensions-3.7.5-1pgdg.rhel7.x86_64
pgpool-II-pg95-3.7.5-1pgdg.rhel7.x86_64
pgpool-II-release-3.7-1.noarch
pgpool-II-pg95-devel-3.7.5-1pgdg.rhel7.x86_64
[root@VM_145_153_centos etc]# rpm -e pgpool-II-pg95-debuginfo-3.7.5-1pgdg.rhel7.x86_64
[root@VM_145_153_centos etc]# rpm -e pgpool-II-pg95-extensions-3.7.5-1pgdg.rhel7.x86_64
[root@VM_145_153_centos etc]# rpm -e pgpool-I
error: package pgpool-I is not installed
[root@VM_145_153_centos etc]# rpm -e pgpool-II
error: package pgpool-II is not installed
[root@VM_145_153_centos etc]# rpm -e pgpool-II-pg95-3.7.5-1pgdg.rhel7.x86_64
error: Failed dependencies:
libpcp.so.1()(64bit) is needed by (installed) pgpool-II-pg95-devel-3.7.5-1pgdg.rhel7.x86_64
pgpool-II-pg95 = 3.7.5 is needed by (installed) pgpool-II-pg95-devel-3.7.5-1pgdg.rhel7.x86_64
[root@VM_145_153_centos etc]# rpm -e pgpool-II-pg95-devel-3.7.5-1pgdg.rhel7.x86_64
[root@VM_145_153_centos etc]# rpm -e pgpool-II-release-3.7-1.noarch
[root@VM_145_153_centos etc]# rpm -e pgpool-II-pg95-3.7.5-1pgdg.rhel7.x86_64
warning: file /etc/pgpool-II/pool_hba.conf: remove failed: No such file or directory
warning: file /etc/pgpool-II/pgpool.conf.sample-stream: remove failed: No such file or directory
warning: file /etc/pgpool-II/pgpool.conf.sample-replication: remove failed: No such file or directory
warning: file /etc/pgpool-II/pgpool.conf.sample-master-slave: remove failed: No such file or directory
warning: file /etc/pgpool-II/pgpool.conf.sample-logical: remove failed: No such file or directory
warning: file /etc/pgpool-II/pgpool.conf: remove failed: No such file or directory
warning: file /etc/pgpool-II/pcp.conf: remove failed: No such file or directory
[root@VM_145_153_centos etc]# rpm -qa |grep pgpool
[root@VM_145_153_centos etc]#