dropdb -- Remove an existing Postgres database
dropdb [ options ] dbname
dropdb destroys an existing Postgres database. The user who executes this command must be a database superuser or the owner of the database.
dropdb is a shell script wrapper around the SQL command DROP DATABASE via the Postgres interactive terminal psql. Thus, there is nothing special about dropping databases via this or other methods. This means that the psql must be found by the script and that a database server is running at the targeted host. Also, any default settings and environment variables available to psql and the libpq front-end library do apply.
To destroy the database demo on the default database server:
$ dropdb demo
DROP DATABASE
To destroy the database demo using the postmaster on host eden, port
5000, with verification and a peek at the underlying query:
$ dropdb -p 5000 -h eden -i -e demo
Database "demo" will be permanently deleted. Are you sure? (y/n) y
DROP DATABASE "demo" DROP DATABASE