Re: The lightbulb just went on...

On Tue, 17 Oct 2000, Tom Lane wrote:

> > and we have not had a crash on vacuum since that happened.  If this
> > sounds consistent with the problem you think Alfred is having,
> 
> Yes, it sure does.
> 
> The patch I have applies atop a previous change in the REL7_0_PATCHES
> branch, so what I would recommend is that you pull the current state of
> the REL7_0_PATCHES branch from our CVS server, and then you can test
> what will shortly become 7.0.3.  There are several other critical bug
> fixes in there since 7.0.2.

Hi Tom.

I have built from the REL7_0_PATCHES tree yesturday and did some testing on the
database.  So far no  crashes during vacuum like I had been seeing with 7.0.2
:).

I am seeing a different problem (and I have seen this with 7.0.2 as well).  If
I run vacuum, sometimes this error pops up in the client appliction during the
vacuum:

ERROR:  RelationClearRelation: relation 1668325 modified while in use

relation 1668325 is a view named "sessions".

what happens to sessions is that it does:

SELECT session_data, id 
FROM   sessions
WHERE  id = ?
FOR UPDATE

.... client does some processing ...

UPDATE sesssions set session_data = ? WHERE id = ?;

(this is where the error happens)

I think part of my problem might be that sessions is a view and not a table,
but it is probably a bug that needs to be noted nonetheless.  I am going to try
converting "sessions" to a view and see if I can reproduce it that way.

Mike