Hi! I have a question with sorting, I don’t understand why in a test a hit with a lower score is ranked before hits with higher scores.
I am using Lucene 5.2.1. Two CustomScoreQuery subqueries on two fields, subquery 1 and subquery 2, and two test cases: case 1: the two calculated custom scores are multiplied by the same factor depending on the date of the match at the end of the customScore method of CustomScoreProvider case 2: the two calculated custom scores are *not* multiplied by the date factor. All tests with the same Sort, by score then by date. Case 1: with date factor: Test 1: subquery 1 only: two hits, doc A (date A) gets the score A1, doc B (date B) gets the score B1: score A1 > score B1, date A < date B, and doc A is ranked before doc B Explanation: doc A score A1 shardIndex=0 fields=[score A1, date A] doc B score B1 shardIndex=0 fields=[score B1, date B] That's correct. Test 2: MUST query subquery 1, subquery 2: the two same docs match: doc A (date A) gets the score A2, doc B (date B) gets the score B2: score A2 *<* score B2, date A < date B, and *doc A is ranked before doc B* Explanation: doc A score A2 shardIndex=0 fields=[score A1, date A] doc B score B2 shardIndex=0 fields=[score B1, date B] *doc A is ranked before doc B although score A2 < score B2 and sorting should use scores A2 and B2, not A1 and B1.* Case 2: without date factor: Test 1: subquery 1 only: doc A (date A) gets the score A1, doc B (date B) gets the score B1: score A1 > score B1, date A < date B, and doc A is ranked before doc B Explanation: doc A score A1 shardIndex=0 fields=[score A1, date A] doc B score B1 shardIndex=0 fields=[score B1, date B] Test 2: MUST query subquery 1, subquery 2: the two same docs match: doc A (date A) gets the score A2, doc B (date B) gets the score B2: score A2 *>* score B2, date A < date B, and doc A is ranked before doc B Explanation: doc A score A2 shardIndex=0 fields=[score A1, date A] doc B score B2 shardIndex=0 fields=[score B1, date B] Using score A1 here works: without the date factor, all the hits of test 2 match subquery 2 in the same way and they get the same sub-score: the explanation shows in this case that the score = field[0] score + the common sub-score of the hits, therefore the sorting is the same by current score as by field[0] score. But, with the date factor, this is no longer true, the sort [Score, date] should use the current scores of test 2 and not those of test 1. Please, could someone enlighten me? Do I make a mistake somewhere? Claude Lepère <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free. www.avg.com <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
