psql --help=variables shows variables treated specially by psql. And it tells you
Usage: psql --set=NAME=VALUE or \set NAME VALUE But some of the variables listed cannot usefully be set, only read, such as DBNAME the currently connected database name HOST the currently connected database server LASTOID the value of last affected OID These can be read in a script, but there is nothing useful you can do with them on the command line. Also, for variables such as HISTCONTROL, IGNOREEOF, PROMPT*, they are more commonly set in psqlrc, not on the command line. Should we trim this list down to variables that are actually useful to set on the command line? I also have some concerns about the listed environment variables. The list of libpq PG* variables is incomplete, and if we're going to curate the list, we surely don't need to show the "not recommended" PGPASSWORD variable. That list probably also needs some ifdefs, since SHELL and TMPDIR don't work on Windows, and PSQL_HISTORY only works when readline support is built. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers