From: Bruce Momjian <maillist@candle.pha.pa.us>
To: lockhart@alumni.caltech.edu
Cc: docs@postgresql.org
Subject: UNION docs
Date: Thu, 18 Mar 1999 21:21:03 -0500 (EST)
Message-ID: <199903190221.VAA13530@candle.pha.pa.us> (raw)
I't unnI don't understand this:
The UNION operator specifies a table derived from a Cartesian product.
The two tables that represent the direct operands of the UNION must
have the same number of columns, and corresponding columns must be
of compatible data types.</para>
Why do you call it a cartesian product. I thought a cartesian product
was tableA x tableB, while UNION is really tableA + tableB, right?
If I am right, can you change the docs? I will leave it as is. Thanks.
--
Bruce Momjian | http://www.op.net/~candle
maillist@candle.pha.pa.us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-docs@postgresql.org
Cc: maillist@candle.pha.pa.us, lockhart@alumni.caltech.edu, docs@postgresql.org
Subject: Re: UNION docs
In-Reply-To: <199903190221.VAA13530@candle.pha.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox