Skip site navigation (1) Skip section navigation (2)

Re: [Dbdpg-general] benchmarking old Pg and DBD::Pg

From: Vlad <marchenko(at)gmail(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Brandon Metcalf <bmetcalf(at)nortel(dot)com>,dbdpg-general(at)gborg(dot)postgresql(dot)org, pgsql-interfaces(at)postgresql(dot)org
Subject: Re: [Dbdpg-general] benchmarking old Pg and DBD::Pg
Date: 2005-04-08 19:22:32
Message-ID: cd70c681050408122241d026c5@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-interfaces
Tom,

Thanks for suggestion - I'm gonna try this patch:

--- dbdimp.c.bak        Wed Apr  6 16:40:20 2005
+++ dbdimp.c    Fri Apr  8 15:21:29 2005
@@ -1415,7 +1415,7 @@
        }
        else if (NULL == currph->bind_type) { /* "sticky" data type */
                /* This is the default type, but we will honor
defaultval if we can */
-               currph->bind_type = pg_type_data(VARCHAROID);
+               currph->bind_type = pg_type_data(UNKNOWNOID);
                if (!currph->bind_type)
                        croak("Default type is bad!!!!???");
        }




On Apr 8, 2005 3:11 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Vlad <marchenko(at)gmail(dot)com> writes:
> > Ideallly a programmer doesn't need to care to specify column type when
> > putting a code like this (assuming C is of an "int" type ):
> 
> > my $sth = $dbh->prepare_cached( "select A from B where C=?");
> > $sth->execute( 123 );
> > ...
> 
> > and DBD::Pg would guess (don't ask me how) the column types and pass
> > it to postgresql so the query executed in most efficient way.
> 
> DBD::Pg shouldn't need to do any such thing --- the backend can do it a
> whole lot better than DBD::Pg could.  What should be happening here is
> that if DBD::Pg hasn't been told a specific type for the parameter, it
> should pass the parameter type to the backend as "UNKNOWN" (yes, there
> is such a type ID) and let the backend try to infer the type.
> 
> There are cases where there's not enough information to infer the type,
> and then the programmer has to provide it, either by writing a cast in
> the query text or by passing the info to bind_param.  It sounds like
> bind_param could do with some work too ... but 80% of this issue would
> go away if UNKNOWN were being used correctly.
> 
>                         regards, tom lane
> 


-- 

Vlad

In response to

Responses

pgsql-interfaces by date

Next:From: Brandon MetcalfDate: 2005-04-08 19:26:39
Subject: Re: [Dbdpg-general] benchmarking old Pg and DBD::Pg
Previous:From: Tom LaneDate: 2005-04-08 19:11:49
Subject: Re: [Dbdpg-general] benchmarking old Pg and DBD::Pg

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group