[JENA-628] TransformFilterPlacement does not always push down through assign/extend when it could

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Jena 2.11.1
• Fix Version/s: Jena 2.11.2
• Component/s: ARQ
• Assignee: Rob Vesse
• Reporter: Rob Vesse
• Created: 27/Jan/14 20:06
• Updated: 19/Apr/14 16:33
• Resolved: 28/Jan/14 14:43

Description

I've noticed a bug in the improved TransformFilterPlacement where it doesn't always do the correct thing when pushing through assign/extend in cases where the placement into BGPs is disabled.

Consider the following example algebra:

(filter (= ?x 123) (assign ((?z 123)) (bgp (?s ?p ?x)) ))

With optFilterPlacementBGP enabled this produces the following improved algebra:

(assign ((?z 123)) (filter (= ?x 123) (bgp (?s ?p ?x)) ))

However with optFilterPlacementBGP disabled this leaves the algebra as is even though it could safely push it through the bind without pushing it into the BGP itself.

I think the fix for this is trivial and I will apply it shortly. I will also look and see if there are other cases where it fails to push down as far as it could.

Issue Links

• is related to: JENA-627 SPARQL query evaluation seems to be broken