BeeeCingU ([log in to unmask]) wrote:
: Subject: Re: Online Quiz, Qtp?
: From: [log in to unmask] (Nigel Campbell)
: Date: 6 Apr 1996 16:56:35 GMT
: Message-ID: <[log in to unmask]>
 
: BeeeCingU ([log in to unmask]) wrote:
 
: I do wonder now if there is any merit to the following:
: In both cases----> Acc a link to b
 
: Select file a if non-defined-item = 'value'
: Select file b if non-defined-itm = 'example'
: Select if defined-item = 99
 
: As opposed to simply stating:
: Select if non-defined-item = 'value' and non-defined-item = 'example' and
: defined-item = 99
 
: I would think the first scenario would achieve the results quicker, but
: according to your earlier message with the 'select file if' being designed
: for parallel linkages(and the noted intellegence of the linking), the
: speed differences may be of no significance or non-existent.
 
Ironically, the Select <file> If does improve performance although if
memory serves this was not the original intent of the design. Certainly
on MPE we used to include release notes on the media. Somewhere around
501 onwards the files included some discussion of Select <file> if etc.
If memory serves the gains were mainly due to the fact that the test
is applied to the read buffer prior to moving the data into the complex
buffer. I've heard some users claim to see no noticeable difference and
others good gains: wether this varies based on the complexity of the selection
criteria or internal tricks some ports added I cannot say.
 
--
Nigel Campbell            Voice: (613) 738-1338 ext 3016   P.O. Box 9707,Stn.T
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http://www.cognos.com                                      CANADA
 
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