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DataSystemsLab / recdb-postgresql

RecDB is a recommendation engine built entirely inside PostgreSQL
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Explain Analyze breaks with recommendation #3

Open Sarwat opened 10 years ago

Sarwat commented 10 years ago

EXPLAIN ANALYZE breaks with a recommendation query. To reproduce the problem, first load the MovieLens dataset and then perform the following queries:

CREATE RECOMMENDER MovieRec ON ml_ratings USERS FROM userid ITEMS FROM itemid EVENTS FROM ratingval USING itemcoscf;

Then execute the following:

EXPLAIN ANALYZE SELECT * FROM ml_ratings RECOMMEND itemid TO userid ON ratingval USING itemcoscf WHERE userid = 1 ORDER BY ratingval LIMIT 10;

The back-end ends unexpectedly and returns a segmentation fault.

Note that EXPLAIN alone works just fine.

TheSoundDefense commented 10 years ago

This is an unexpected side effect of the latest optimization (enhanced user filtering). Working on a fix.

jmealo commented 8 years ago

@TheSoundDefense Any update on this? Kudos on your great work!