[Dovecot] do Dovecot userdb and passwd filles need to be postmap'd

Hi all

I am unsure if dovecot files like userdb and passwd also need to be postmap'd

i.e. postmap userdb or userdb passwd

when I use the typical data format for creating userdp postmap outputs the error

postmap userdb
postmap: warning: userdb, line 1: expected format: key whitespace value

a clarification is welcome

greetings

hans