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Re: Dynamic time statements?

From: Richard Newman <r.newman@reading.ac.uk>
Date: Sat, 25 Jun 2005 10:05:16 +0100
Message-Id: <14BECBB8-288E-4A83-BF09-F426C3BE60A2@reading.ac.uk>
Cc: Danny Ayers <danny.ayers@gmail.com>, semantic-web@w3.org
To: Jan Algermissen <jalgermissen@topicmapping.com>

That would be my immediate approach, rather than having a mutating  
statement in the store... it also allows one to ask "who's presenting  
tomorrow at 10?" without any changes.

Methinks a store perhaps needs specialised indices for datatypes to  
speed this kind of thing up.

-R

On 25 Jun 2005, at 09:30, Jan Algermissen wrote:

>
> Danny,
>
> why don;tyou just put the current time in the query?
>
> ..where presentation-start <= "2005-06-24T15:05:00Z"
>     and prtesenation-end == null
>
> (forgive me the SQL like query, not yet good enough at sparql).
>
> (This brings up an issue I have with existing RDF databases: all of  
> them seem
> not to be able to recognize literal datatypes for operator  
> 'binding'. For
> example: the <= operator should work differently for dates than for  
> int and yet
> for strings).
>
> If you have a million+ dates, doing the <= operation with a full  
> scan is
> starting to be rediculous.
>
> Thoughts?
>
> Jan
Received on Saturday, 25 June 2005 09:05:28 GMT

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