I wonder if you shut down the postmaster and restart if that would make it work again. I can't imagine where it would store table size information if the area is read-only. Adding data, full vacuum, restart postmaster should allow read-only databases.
--------------------------------------------------------------------------- > I'm curious as to whether anybody has gotten PostgreSQL to work with a > database that lives on some sort of read-only medium...like a CD. > > I've looked around in the newsgroups and I've seen a comment by Bruce > Momjian that it can't currently be done...and I've seen a different comment > by Tom Lane that he thought that it probably could...So...I dunno. > > I've taken a database and set the read-only attributes on its files and > tried to access it via psql...and couldn't...it complained about not being > able to open pg_class. > > SO...I dug around through the code a little and found where the error was > coming from and changed the code so that if the open attempt with O_RDWR > fails, the code tries again with O_RDONLY. This was in md.c...in the mdopen > function. > > This did work....I was then able to open the database and do queries and > whatnot. Trying to insert into the table didn't give any errors...until I > tried to select the record back out, at which time it started giving me > errors such as: > > ERROR: cannot write block 7548 of pole: Permission denied > > At that point, it seems that your screwed...in that even if you shut down > postgres and restart it, somewhere it knows that that database has data that > needs to be written to disk, and it refuses to continue until it does so. > > OTHER than that one problem...Is anyone aware of any other problems that my > change might cause? To be really useful, it would be necessary to go > through and make additional changes so that it can recover from a failed > write to the "read-only" database. But it seems like it would be okay as > long as you carefully avoid changing the database. > > > > ---------------------------(end of broadcast)--------------------------- > TIP 6: Have you searched our list archives? > > http://archives.postgresql.org > -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 853-3000 + If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania 19026 ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
