330b84d8c4
pg_dump has always handled the public schema in a special way when it comes to the "--clean" option. To wit, we do not drop or recreate the public schema in "normal" mode, but when we are run in "--clean" mode then we do drop and recreate the public schema. When running in "--clean" mode, the public schema is dropped and then recreated and it is recreated with the normal schema-default privileges of "nothing". This is unlike how the public schema starts life, which is to have CREATE and USAGE GRANT'd to the PUBLIC role, and that is what is recorded in pg_init_privs. Due to this, in "--clean" mode, pg_dump would mistakenly only dump out the set of privileges required to go from the initdb-time privileges on the public schema to whatever the current-state privileges are. If the privileges were not changed from initdb time, then no privileges would be dumped out for the public schema, but with the schema being dropped and recreated, the result was that the public schema would have no ACLs on it instead of what it should have, which is the initdb-time privileges. Practically speaking, this meant that pg_dump with --clean mode dumping a database where the ACLs on the public schema were not changed from the default would, upon restore, result in a public schema with *no* privileges GRANT'd, not matching the state of the existing database (where the initdb-time privileges would have been CREATE and USAGE to the PUBLIC role for the public schema). To fix, adjust the query in getNamespaces() to ignore the pg_init_privs entry for the public schema when running in "--clean" mode, meaning that the privileges for the public schema would be dumped, correctly, as if it was going from a newly-created schema to the current state (which is, indeed, what will happen during the restore thanks to the DROP/CREATE). Only the public schema is handled in this special way by pg_dump, no other initdb-time objects are dropped/recreated in --clean mode. Back-patch to 9.6 where the bug was introduced. Discussion: https://postgr.es/m/3534542.o3cNaKiDID%40techfox
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. PostgreSQL has many language interfaces, many of which are listed here: http://www.postgresql.org/download See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.