Are there any mechanisms in redland/rasqal for reducing query time variance 
depending on statement order in a SPARQL query.

For example a query that contains an exact literal match as the first 
statement, may take a few ms to execute and return a single result.

But if the statement order is changed so that the first statement returns 
1000's of potential matches then the query time may increases to tens of 
seconds to return the same single result.

I'm trying to find where in the code the execution engine walks the syntax 
tree, and I'm wondering of this could be modified to use a cost based planner 
that could modify the execution order of statements?

Andy
_______________________________________________
redland-dev mailing list
[email protected]
http://lists.librdf.org/mailman/listinfo/redland-dev

Reply via email to