On Mon, Jun 14, 2010 at 05:17, John T. Dow <john@johntdow.com> wrote:
> I was talking to a friend (Joe Newcomer) who said that Unix doesn't have mandatory file locks and he guessed that the
empty,system, read only files I saw at my client's site were unix-like lock files.
They are not. They are regular relation files.
> To test that, on my home development computer I typed this command in the base\16384 diretory:
>
> attrib +r 2611
>
> That is, I made 2611 read only.
>
> Sure enough, pgadmin can't display the columns for any of the tables. I get "permission denied" for 2611.
>
> And sure enough, the Java application runs fine and indeed is able to export the table definition, complete with
columns.
Most likely because pgadmin tries to fetch all information about the
table, including toast relations, whereas the java application only
fetches the information it actually needs.
> So this is exactly the behavior observed at my client's site.
>
> Apparently the problem boils down to this question: how did some of the files get set to be system and read only?
Yes. That would be very interesting to know. PostgreSQL never
(intentionally) sets these flags, so they must've come from something
else.
If you remove those flags, do they eventually come back on? Is so, you
probably want to install some level of monitoring tool (process
monitor from sysinternals is recommended) to figure out when that gets
set.
> Anybody ever seen this?
Well, at the risk of sounding like a broken clock, yes - with
antivirus or antispyware that sets the flag on things they find
suspicious.
--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/