Re: Cached Queries Problem

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On Apr 28, 2005, at 9:30 AM, Perrin Harkins wrote:
> David Christensen said:
>>> Have you determined where the name dbdpg_13 comes from?  That might 
>>> be
>>> a clue.
>>
>> I believe it would be the 13th query that DBD::Pg has cached thus far.
>
> What I'm suggesting is that the code which generates that name may be
> where  the caching problem is, so finding it would be useful.

I don't know.  My gut right now is that it's Ima::DBI, or it's 
DBD::Pg's implementation of prepare_cached.  I believe I've fixed the 
problem now in any case.

>> One thing that I am doing is trying to preload my Class::DBI subclass
>> in apache (just via a use statement). I'm using one of the table-setup
>> utility functions rather than hard-coding the fields in, so that may 
>> be
>> the cause of the problem -- we obviously have to query the database
>> before we can pull info out of the system tables.
>
> This should be safe if you are using my mod_perl code from the wiki 
> that
> overrides db_Main().  You can check by turning on debugging for
> Apache::DBI.  You should see warnings about skipping the cache during
> server startup.

I am using code you provided from the wiki for db_Main.  But I 
neglected to close the connection after the initial load.  So I think 
we ended up with a "shared" dbi handle between apache processed.  
(Obviously a big no-no).  Once I added a 
MyClass::DBI->db_Main->disconnect to the end of the startup file, it 
seemed to work ok.  (In any case, I haven't come across it yet -- I've 
done similar actions which have triggered the errors before, so that's 
hopeful.)

Thanks all.  I'll get back if things are not fixed, but for right now 
it's looking good.

David