"Brendan Jurd" <direvus@gmail.com> writes:
> Most people wanting to learn about which system functions are
> available will be surely be going to the manual, not using \df?
I think people use \df all the time to check the argument list, verify
whether they remember the function name correctly, etc. It's not for
"learning about" stuff you never heard of, it's for remembering details
(as indeed is the usage for user-defined functions too).
regards, tom lane