Postgres: Best way to move data from public schema of one DB to new schema of another DB

Question

I am new to Postgres and just discovered that I cannot access data of different databases in one SQL query. And also learned the concept of schema in Postgres.

Now, I ha

Answer 1

Export "public" from db2 (skipping grants and ownership):

pg_dump -xO -n public db2 > db2.sql

The exported file will set up the search path (somewhere near the top):

SET search_path = public, pg_catalog;

change it to:

CREATE SCHEMA IF NOT EXISTS new_schema;
SET search_path = new_schema, pg_catalog;

Import to db1 as usual:

psql db1 < db2.sql

You'll probably want to move everything from public to a new schema in db1, first.

If the schema is already set up in db1, you can do the transfer in one go:

pg_dump -xO -n public db2 | sed 's/search_path = public/search_path = new_schema/' | psql db1

Wouldn't recommend that without a lot of testing, of course.