یکم دیگه جستجو کردم :
dropdb accepts the following command-line arguments:
dbname Specifies the name of the database to be removed.
-e
--echo
Echo the commands that
dropdb generates and sends to the server.
-i
--interactive Issues a verification prompt before doing anything destructive.
-q --quiet Do not display a response.
dropdb also accepts the following command-line arguments for connection parameters:
-h host --host host Specifies the host name of the machine on which the server is running. If the value begins with a slash, it is used as the directory for the Unix domain socket.
-p port --port port Specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections.
-U username --usernameusername User name to connect as -W --password Force password prompt.
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