Re: SHOULD use POST for expensive queries?

On Jan 18, 2006, at 10:26 AM, Seaborne, Andy wrote:

>>  Even very sophisticated query analysis can't tell  you which RDF  
>> datasets are expensive to assemble.
>
> Very true.  It's not just the query that determines whether it will  
> be expensive - it's the dataset as well (and the sever load).

Actually, now that I think about it, that's not *entirely* true. Real  
(as opposed to toy) database cost models include table size, and even  
for arbitrary 3rd party graphs, with clever caching and use of HTTP,  
a SPARQL query analyzer could make some good guesses (so, imagine the  
ideal case: all the graphs are cached locally and known to be fresh),  
so it's not as bad as I made it seem.

But in the common or pathological cases (where all graphs are  
unknown, uncached, and have to be retrieved from arbitrary origin  
servers), well... -shudder-.

Cheers,
Kendall
--
You're part of the human race
All of the stars and the outer space
Part of the system again

Received on Wednesday, 18 January 2006 15:39:39 UTC