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

Re: When I select a single column, can I prevent getting a list of one-element tuples?

From: Nick Cash <nick(dot)cash(at)npcinternational(dot)com>
To: "psycopg(at)postgresql(dot)org" <psycopg(at)postgresql(dot)org>
Subject: Re: When I select a single column, can I prevent getting a list of one-element tuples?
Date: 2012-06-19 20:19:08
Message-ID: 846C3A8E860C4344B567D813B63AA51D0AE1F9AF@CH1PRD0610MB356.namprd06.prod.outlook.com (view raw or flat)
Thread:
Lists: psycopg
You could always make use of tuple-unpacking and try something like

[element for (element,) in cursor.fetchall()]

It feels slightly more pythonic to me, though not by much.

Thanks,
Nick Cash

-----Original Message-----
From: psycopg-owner(at)postgresql(dot)org [mailto:psycopg-owner(at)postgresql(dot)org] On Behalf Of W. Matthew Wilson
Sent: Tuesday, June 19, 2012 13:36
To: Daniele Varrazzo
Cc: psycopg(at)postgresql(dot)org
Subject: Re: [psycopg] When I select a single column, can I prevent getting a list of one-element tuples?

On Sun, Jun 17, 2012 at 12:32 PM, Daniele Varrazzo <daniele(dot)varrazzo(at)gmail(dot)com> wrote:

> No, there's nothing like this. For me, any attempt to add a feature 
> and let the user choose whether to return one-column queries just as 
> lists or as one-item tuples (a cursor subclass? a function?) seems 
> more verbose than the [r[0] for r in cur] or map(itemgetter(0), cur) 
> to get the data the way you want.

Thanks for the reply!  Mostly I wanted to make sure there wasn't already a standard solution out there.

For me, it just feels goofy to write something like [row[0] for row in cursor.fetchall()], but I understand where you are coming from.

I like the cursor subclass idea so maybe I'll take a shot at something like that.

Matt

--
W. Matthew Wilson
matt(at)tplus1(dot)com
http://tplus1.com

--
Sent via psycopg mailing list (psycopg(at)postgresql(dot)org) To make changes to your subscription:
http://www.postgresql.org/mailpref/psycopg



In response to

psycopg by date

Next:From: Federico Di GregorioDate: 2012-06-20 13:17:46
Subject: Re: Patches to add support for tox and Travis CI tools to psycopg2
Previous:From: W. Matthew WilsonDate: 2012-06-19 18:36:11
Subject: Re: When I select a single column, can I prevent getting a list of one-element tuples?

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