为什么用不了呢？

wsp0108

[postgres@localhost postgres]$ psql mysql
bash: psql: command not found
[postgres@localhost postgres]$ postmaster -i &
[1] 6669
[postgres@localhost postgres]$ bash: postmaster: command not found

[1]+  Exit 127                postmaster -i
[postgres@localhost postgres]$ su root
Password:
[root@localhost postgres]# ps -ax|grep postmaster
6546 ?        S      0:00 postmaster -i
6702 pts/2    S      0:00 grep postmaster