Postgresql – Use pg_dump with postgis extensions

backuppg-dumppostgresqlpostgresql-9.4

I'm using Postgres 9.4. I'm trying to dump a database (both the schema and the actual data) with the PostGIS extensions (set up using CREATE EXTENSION):

$ pg_dump prescribing -U prescribing -h localhost -Fc > prescribing.dump
Password:

But when I type in the db password, I see this:

pg_dump: [archiver (db)] query failed: ERROR:  permission denied for schema topology
pg_dump: [archiver (db)] query was: LOCK TABLE topology.topology IN ACCESS SHARE MODE

How can I dump this database?

UPDATE: it says these tables are owned by postgres:

 public | frontend_sha                               | table             | prescribing
 public | geography_columns                          | view              | postgres
 public | geometry_columns                           | view              | postgres
 public | pg_stat_statements                         | view              | postgres
 public | raster_columns                             | view              | postgres
 public | raster_overviews                           | view              | postgres
 public | spatial_ref_sys                            | table             | postgres
 public | vw_chemical_summary_by_ccg                 | materialized view | prescribing

Maybe I could just dump the other tables, and import them into another database set up in the same way? Or maybe I could run pg_dump as a superuser? But if I try pg_dump prescribing then it still asks me for a password, and I don't know what that should be.

Best Answer

What about using -T modifier for pg_dump to skip those tables?

For example -T topology.*

Related Solutions

PostgreSQL – pg_restore Error: Schema ‘public’ Already Exists

The error is harmless but to get rid of it, I think you need to break this restore into two commands, as in:

dropdb -U postgres mydb && \
 pg_restore --create --dbname=postgres --username=postgres pg_backup.dump

The --clean option in pg_restore doesn't look like much but actually raises non-trivial problems.

For versions up to 9.1

The combination of --create and --clean in pg_restore options used to be an error in older PG versions (up to 9.1). There is indeed some contradiction between (quoting the 9.1 manpage):

--clean Clean (drop) database objects before recreating them

and

--create Create the database before restoring into it.

Because what's the point of cleaning inside a brand-new database?

Starting from version 9.2

The combination is now accepted and the doc says this (quoting the 9.3 manpage):

--clean Clean (drop) database objects before recreating them. (This might generate some harmless error messages, if any objects were not present in the destination database.)

--create Create the database before restoring into it. If --clean is also specified, drop and recreate the target database before connecting to it.

Now having both together leads to this kind of sequence during your restore:

DROP DATABASE mydb;
...
CREATE DATABASE mydb WITH TEMPLATE = template0... [other options]
...
CREATE SCHEMA public;
...
CREATE TABLE...

There is no DROP for each individual object, only a DROP DATABASE at the beginning. If not using --create this would be the opposite.

Anyway this sequence raises the error of public schema already existing because creating mydb from template0 has imported it already (which is normal, it's the point of a template database).

I'm not sure why this case is not handled automatically by pg_restore. Maybe this would cause undesirable side-effects when an admin decides to customize template0 and/or change the purpose of public, even if we're not supposed to do that.

Postgresql – pg_dump does not honor -n

When dumping a schema with the mentioned command, as postgres user:

pg_dump -f file.sql -F plain --inserts -n schemaname database

it produces a file whose basic structure looks like:

-- various SET commands
CREATE SCHEMA schemaname;

ALTER SCHEMA schemaname OWNER TO ownername;

SET search_path = schemaname, pg_catalog;

CREATE TABLE tablename(...) ...

ALTER TABLE schemaname.tablename OWNER TO ownername;

COPY tablename (columns...) FROM stdin;
data...
\.

The fact that search_path is set to the newly created schema implies that the CREATE TABLE and COPY statements that follow will happen in that schema and not in the public schema.

Or SET search_path would have to fail, which shouldn't happen even if the creation of the schema just above in the script failed. If schemaname does not exist, the next schema tried would be pg_catalog and CREATE TABLE would refuse to write into it, and after that there's no next schema in the search path, and in particular not public.

It's hard to imagine what mishappening could cause the above script to end up creating and populating anything in the public schema.

Best Answer

Related Solutions

PostgreSQL – pg_restore Error: Schema ‘public’ Already Exists

Postgresql – pg_dump does not honor -n

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