[PATCH] pg_upgrade fails when postgres/template1 isn't in default tablespace - Mailing list pgsql-hackers

error while copying relation "pg_catalog.pg_largeobject" ("/srv/ssd/PG_9.3_201306121/1/12023" to "/PG_9.4_201409291/1/12130"): No such file or directory

Turns out this happens when either the "postgres" or "template1" databases have been moved to a non-default tablespace. pg_dumpall does not dump attributes (such as tablespace) for these databases; pg_upgrade queries the new cluster about the tablespace for these relations and builds a broken destination path for the copy/link operation.

The least bad solution seems to be generating ALTER DATBASE SET TABLESPACE commands for these from pg_dumpall. Previously a --globals-only dump didn't generate psql \connect commands, but you can't run SET TABLESPACE from within the same database you're connected to. So to move "postgres", it needs to connect to "template1" and vice versa. That seems fine for the purpose of pg_upgrade which can assume a freshly created cluster with both databases intact.

Alternatively, we could allow SET TABLESPACE in the current database, which seems less ugly to me. A code comment says "Obviously can't move the tables of my own database", but it's not obvious to me why. If I'm the only connected backend, it seems that any caches and open files could be invalidated. But I don't know how big of an undertaking that would be.

While working on this, I also noticed other things that pg_dumpall (and this pg_upgrade) misses:

* Nothing at all is dumped for the template0 database, although ACLs, settings and the tablespace can be changed by the user

* template1 & postgres databases retain ACLs and settings, but not attributes like TABLESPACE or CONNECTION LIMIT. Other attributes like LC_COLLATE and LC_CTYPE can't be changed without recreating the DB, but those don't  matter for the pg_upgrade case anyway.

It seems those would be good material for another patch?

Regards,

Marti Raudsepp