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

Re: Different responses to description request between Mac and Linux

From: Jerry Schneider <jerry57(at)gmail(dot)com>
To: Daniele Varrazzo <daniele(dot)varrazzo(at)gmail(dot)com>
Cc: psycopg(at)postgresql(dot)org
Subject: Re: Different responses to description request between Mac and Linux
Date: 2011-03-22 03:49:41
Message-ID: 4D881C55.5070204@iplantcollaborative.org (view raw or flat)
Thread:
Lists: psycopg
On 3/21/11 7:24 PM, Daniele Varrazzo wrote:
> On Tue, Mar 22, 2011 at 12:51 AM, Jerry Schneider<jerry57(at)gmail(dot)com>  wrote:
>> I am working on extending a library for RobotFramework and added a keyword
>> for column description retrieval but noticed that when I run it on Mac OS X
>> 10.6 I am getting:
>> Column(name='id', type_code=20, display_size=None, internal_size=8,
>> precision=None, scale=None, null_ok=None)
>> but when I run the exact same test against the exact same database from an
>> Ubuntu 10.10 Linux box I am getting:
>> ('id', 20, None, 8, None, None, None)
>>
>> The only difference that I can find is that the Mac box is running psycopg2
>> 2.4 installed via (python setup.py install) while the Ubuntu box is running
>> psycopg2 2.2.1 installed via package management.  Is it possible that this
>> version difference is what is accounting for the response difference?
> Yes: from 2.4 cursor.description is provided as namedtuple if
> available (http://initd.org/psycopg/docs/cursor.html#cursor.description).
>
> Named tuple are accessible as regular tuple via indexing and hash the
> same, see<http://docs.python.org/library/collections.html#collections.namedtuple>
> so there should be no backward compatibility problem (but if you have
> found any... let's talk about that).
>
> If your concern are doctest (the first thing that comes to mind that
> may have been broken by the namedtuple... but that's because doctests
> are a broken idea) you can use tuple(x) to transform a namedtuple back
> in a regular tuple.
>
> -- Daniele

Thanks Daniele, that is what I needed to know.  No these aren't being 
used for doctests, but rather verification tests that the columns are 
setup/defined correctly after a database upgrade.  I will adapt the 
keyword I was creating using the connections.namedtuple.

jer

-- 
Jerry Schneider
QA Manager
iPlant Collaborative
BIO5 Research Institute
University of Arizona
Linux registered user #475536
Ubuntu registered user #28583


In response to

psycopg by date

Next:From: Federico Di GregorioDate: 2011-03-25 09:22:10
Subject: Re: double free issue in 2.4 (and previous versions)
Previous:From: Daniele VarrazzoDate: 2011-03-22 02:24:01
Subject: Re: Different responses to description request between Mac and Linux

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