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From: "Randolf Richardson, DevNet SysOp 29" <rr@8x.ca>
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Subject: Re: Expressional Indexes
Date: Mon, 17 Nov 2003 05:31:07 +0000 (UTC)
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[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/

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