Re: Copying DB data from Heroku Postgresql to local server

2013-01-25 Thread Peter van Hardenberg
Okay! Tom Lane has now fixed this and future Postgres releases will not exhibit this behaviour. The commit should land shortly. Thanks for the report! On Mon, Jan 21, 2013 at 11:04 PM, Peter van Hardenberg p...@heroku.comwrote: Thanks for the extra reply Nickolay. I think I came up with a

Re: Copying DB data from Heroku Postgresql to local server

2013-01-21 Thread Peter van Hardenberg
Hm - that's an interesting one. I've never seen Rails pick up a schema change without a restart before. I suspect the complexity cost and overhead of monitoring the schema would outweigh the benefits of saving a process restart. That said, it's weird that even if you recreate tables with the same

Re: Copying DB data from Heroku Postgresql to local server

2013-01-21 Thread Nickolay Kolev
I don't think this is it. Even if there are no schema changes, the same behaviour can be observed. Actually Rails *will* pick up schema changes (e.g. as introduced by migrations) when running in development mode. I have only seen this with Postgres and only when loading a dump. If true for all

Re: Copying DB data from Heroku Postgresql to local server

2013-01-21 Thread Keenan Brock
I wonder if your functions will fail as well. Will vacuum or statistics recompiles all the stored procedures and functions? Google didn't show me any more information on this one. I remember in Sybase, changing the statistics on a table too much used to reek havoc, slowing queries down by over

Re: Copying DB data from Heroku Postgresql to local server

2013-01-21 Thread Peter van Hardenberg
So here's the deal - when you prepare a statement, Postgres compiles it down internally for performance. This means that it doesn't target the table by name anymore, but by it's internal OID. This guarantees nice properties like query stability, but apparently doesn't play well with schema

Re: Copying DB data from Heroku Postgresql to local server

2013-01-21 Thread Nickolay Kolev
I looked at the thread at pgsql-hackers. It seems that Tom Lane overlooked the dump/restore part. A picture is worth a thousand words: http://grozdova.com/psql-missing-relation-after-dump-restore.png I am not sure if this is intended behaviour or not, but it should become clear at the thread

Re: Copying DB data from Heroku Postgresql to local server

2013-01-21 Thread Peter van Hardenberg
Thanks for the extra reply Nickolay. I think I came up with a pretty minimal test-case based on your example. On Mon, Jan 21, 2013 at 10:18 PM, Nickolay Kolev nmko...@gmail.com wrote: I looked at the thread at pgsql-hackers. It seems that Tom Lane overlooked the dump/restore part. A picture