From: Randolf Richardson, DevNet SysOp 29 <rr@8x.ca>
To: pgsql-sql@postgresql.org
Subject: Re: Expressional Indexes
Date: Mon, 17 Nov 2003 05:31:07 +0000 (UTC)
Message-ID: <Xns9435D8D7BF744rr8xca@200.46.204.72> (raw)
References: <7141E2A2-04BE-11D8-81AE-0005029FC1A7@myrealbox.com>
<200310221239.58302.josh@agliodbs.com>
<18349.1066851898@sss.pgh.pa.us>
<200310221322.26013.josh@agliodbs.com>
[sNip]
>> I have been considering using "calculated index" or "computed index"
>> but dunno if that really conveys anything.
>
> Well, "Expression Indexes" is the most accurate. Or "Expression-Based
> Indexes."
What is the proposed definition of an "Expression Index?"
When I see this term, I get the impression I can create an index that's
based on the results of a SELECT, such as for selecting data with specific
values or ranges of values...
For example, if I want to index on a date field but only have the index
keep track of the most recent 30 days (and then create a secondary index for
all dates) so as to improve performance on more heavily loaded systems.
Am I understanding this new terminology correctly? Thanks in advance.
--
Randolf Richardson - rr@8x.ca
Inter-Corporate Computer & Network Services, Inc.
Vancouver, British Columbia, Canada
http://www.8x.ca/
This message originated from within a secure, reliable,
high-performance network ... a Novell NetWare network.
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-sql@postgresql.org
Cc: rr@8x.ca
Subject: Re: Expressional Indexes
In-Reply-To: <Xns9435D8D7BF744rr8xca@200.46.204.72>
* 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