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

Re: Incremental results from libpq

From: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
To: "Goulet, Dick" <DGoulet(at)vicr(dot)com>
Cc: Frank van Vugt <ftm(dot)van(dot)vugt(at)foxi(dot)nl>, Greg Stark <gsstark(at)mit(dot)edu>,pgsql-interfaces(at)postgresql(dot)org
Subject: Re: Incremental results from libpq
Date: 2005-11-13 15:24:01
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-interfaces
Goulet, Dick wrote:

> 	For a simple "select * from <table_name>" even with a where
> clause you may simply get the results one row at a time as they are
> extracted & deemed appropriate for the result set.  But if you've
> included a group by or order by clause, or a union/intersect/minus
> clause then yes, the database will assemble results before sending them
> to the client.

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.

Alvaro Herrera                      
The PostgreSQL Company - Command Prompt, Inc.

In response to


pgsql-interfaces by date

Next:From: Tom LaneDate: 2005-11-13 15:46:35
Subject: Re: Incremental results from libpq
Previous:From: Goulet, DickDate: 2005-11-11 20:17:10
Subject: Re: Incremental results from libpq

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group