How can I drop all the tables in a PostgreSQL database?

How can I drop all tables in PostgreSQL, working from the command line?

I don’t want to drop the database itself, just all tables and all the data in them.

If all of your tables are in a single schema, this approach could work (below code assumes that the name of your schema is public)

DROP SCHEMA public CASCADE;
CREATE SCHEMA public;

If you are using PostgreSQL 9.3 or greater, you may also need to restore the default grants.

GRANT ALL ON SCHEMA public TO postgres;
GRANT ALL ON SCHEMA public TO public;