Thread: 2 distinct connections

2 distinct connections

From
Martin Marques
Date:
We're working on a project using PHP and PostgreSQL, mainly trying to work
in an OOP fashion. The project has quite a good amount of code, and a DB
Object called DB_Bib that has all the query methods. I also have a generic
DB object (DB_Main) which has code to establesh the connection, and from
which my DB_bib Inerits the DB connection.

The thing is that I made a new class called DB_Debug which also inherits
from DB_Main, and is there to have debugging data inserted into a table in
the database.

I noticed that when the two objects are started (they both call the
connection method using the same connection string) php doesn't
initiate to distinct connections, but 1 connection within commands from
both objects get passed to the DB server.

The problem is that query commands from the DB_Debug object and from the
DB_Bib object get mixed up in the same connection, making it deficult to
know when to make a commit.

Is there a way to fix this without having to change the connection string?

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Lic. Martín Marqués         |   SELECT 'mmarques' ||
Centro de Telemática        |       '@' || 'unl.edu.ar';
Universidad Nacional        |   DBA, Programador,
     del Litoral             |   Administrador
---------------------------------------------------------

Re: 2 distinct connections

From
Cornelia Boenigk
Date:
Hi Martin

Did you try passing the constant PGSQL_CONNECT_FORCE_NEW to the
Debug-connect?

regards
Conni

Re: 2 distinct connections

From
Martin Marques
Date:
On Sat, 27 May 2006, Cornelia Boenigk wrote:

> Hi Martin
>
> Did you try passing the constant PGSQL_CONNECT_FORCE_NEW to the
> Debug-connect?

Excelente. I forgot to say that I'm working with PEAR::DB, and just found
this in DB/pgsql.php:

         if (isset($dsn['new_link'])
             && ($dsn['new_link'] == 'true' || $dsn['new_link'] === true))
         {
             if (version_compare(phpversion(), '4.3.0', '>=')) {
                 $params[] = PGSQL_CONNECT_FORCE_NEW;
             }
         }

I always forget to "use the source Luke!" :-)

thanks!

--
  21:50:04 up 2 days,  9:07,  0 users,  load average: 0.92, 0.37, 0.18
---------------------------------------------------------
Lic. Martín Marqués         |   SELECT 'mmarques' ||
Centro de Telemática        |       '@' || 'unl.edu.ar';
Universidad Nacional        |   DBA, Programador,
     del Litoral             |   Administrador
---------------------------------------------------------

Re: 2 distinct connections

From
Volkan YAZICI
Date:
On May 27 09:37, Martin Marques wrote:
> We're working on a project using PHP and PostgreSQL, mainly trying to work
> in an OOP fashion. The project has quite a good amount of code, and a DB
> Object called DB_Bib that has all the query methods. I also have a generic
> DB object (DB_Main) which has code to establesh the connection, and from
> which my DB_bib Inerits the DB connection.
>
> The thing is that I made a new class called DB_Debug which also inherits
> from DB_Main, and is there to have debugging data inserted into a table in
> the database.
>
> I noticed that when the two objects are started (they both call the
> connection method using the same connection string) php doesn't
> initiate to distinct connections, but 1 connection within commands from
> both objects get passed to the DB server.
>
> The problem is that query commands from the DB_Debug object and from the
> DB_Bib object get mixed up in the same connection, making it deficult to
> know when to make a commit.

As Cornelia Boenig suggested, you can force pg_connect() to establish a new
connection on every call. Also if you don't want to exhaust max_connections
limit, you can serialize queries using semaphores (or mutex).


Regards.