To: Alvaro Herrera <alvherre@commandprompt.com>
cc: "Goulet, Dick" <DGoulet@vicr.com>, Frank van Vugt <ftm.van.vugt@foxi.nl>,
	Greg Stark <gsstark@mit.edu>, pgsql-interfaces@postgresql.org
Subject: Re: Incremental results from libpq 
In-reply-to: <20051113152401.GB31570@surnet.cl> 
References: 
 <4001DEAF7DF9BD498B58B45051FBEA6502EF5389@25exch1.vicorpower.vicr.com>
	<20051113152401.GB31570@surnet.cl>
Comments: In-reply-to Alvaro Herrera <alvherre@commandprompt.com>
	message dated "Sun, 13 Nov 2005 12:24:01 -0300"
Date: Sun, 13 Nov 2005 10:46:35 -0500
Message-ID: <4304.1131896795@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Alvaro Herrera <alvherre@commandprompt.com> writes:
> So, what happens with the 1/x query Tom mentioned?  How does Oracle
> handles that situation?  Notice there's no special clause in the query
> itself, so if it's extracted and returned, there's no way for the server
> to know that there's a problem laying ahead.

>> Also Oracle supports cursors which allow you to pop one or more
>> rows off of the result set at a time.  The way Postgresql returns data
>> all at once is different. 

> Postgres supports cursors too.  The Qt guys, and everyone else, could be
> using it to get incremental results right now, no libpq mods necessary.

Note that in this context, it's really pretty misleading to make any
blanket assertions about "Postgres does this" or "Postgres does that".
The behavior is partially determined by the client-side code, and
might well differ depending on which client library you are using,
as well as how you are using it.

For all I know, similar remarks might apply to Oracle.  Do they support
more than one application-side API?

			regards, tom lane