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Blazegraph Query optimizer pessimises query Deprecated_statements
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Blazegraph's query optimizer orders operations in a way that leads to a timeout in some cases where disabling the optimizer returns a result within seconds.

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JanZerebecki raised the priority of this task from to Needs Triage.
JanZerebecki updated the task description. (Show Details)
JanZerebecki added subscribers: JanZerebecki, Aklapper.
Smalyshev triaged this task as Medium priority.Sep 12 2016, 10:45 PM

The query is:

SELECT ?wdLabel ?wdPLabel ?valueLabel ?wd ?wdP ?wds ?value 
  # hint:Query hint:optimizer "None" .
  ?wds wikibase:rank wikibase:DeprecatedRank .
  ?wd ?p ?wds .
  ?wds ?v ?value .
  ?wdP wikibase:statementProperty ?v .
  ?wdP wikibase:claim ?p .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .

Works with optimizer disabled, times out with optimizer enabled.