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I have a shell script (sh) where I create a user and import data to a postgres database <snip> su -c "createuser -A -D -P $PG_user" postgres su -c "psql -d$PG_database -h localhost -U$PG_user -W -f postgresql.sql " postgres </snip> when the script executes those command, it ask for a password, how could I do this without have to enter the passwd, I would like that