Execute .sql schema in psycopg2 in Python

I can't reply to comments of the selected answer by lack of reputation, so i'll make an answer to help with the COPY issue.

Depending on the volume of your DB,pg_dump --inserts outputs INSERTs instead of COPYs


You can just use execute:

with self.connection as cursor:
    cursor.execute(open("schema.sql", "r").read())

though you may want to set psycopg2 to autocommit mode first so you can use the script's own transaction management.

It'd be nice if psycopg2 offered a smarter mode where it read the file in a statement-at-a-time and sent it to the DB, but at present there's no such mode as far as I know. It'd need a fairly solid parser to do it correctly when faced with $$ quoting (and its $delimiter$ variant where the deimiter may be any identifier), standard_conforming_strings, E'' strings, nested function bodies, etc.

Note that this will not work with:

  • anything containing psql backslash commands
  • COPY .. FROM STDIN
  • very long input

... and therefore won't work with dumps from pg_dump