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Update matching_candidates_in_table() to treat all conditions similar

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Fixed also that the 'with_found_constraint parameter' to
matching_candidates_in_table() is as documented: It is now true only
if there is a reference to a previous table in the WHERE condition for
the current examined table (as it was originally documented)

Changes in test results:
- Filtered was 25% smaller for some queries (expected).
- Some join order changed (probably because the tables had very few rows).
- Some more table scans, probably because there would be fewer returned
  rows.
- Some tests exposes a bug that if there is more filtered rows, then the
  cost for table scan will be higher. This will be fixed in a later commit.
This commit is contained in:
Monty
2021-10-07 20:15:34 +03:00
committed by Sergei Petrunia
parent dc2f0d138d
commit b67144893a
41 changed files with 286 additions and 269 deletions
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2
mysql-test/main/join_nested.result
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@ -1064,7 +1064,7 @@ t0.b=t1.b AND
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t0 ref idx_a idx_a 5 const 2 100.00
1 SIMPLE t9 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t1 ALL idx_b NULL NULL NULL 7 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t1 ALL idx_b NULL NULL NULL 7 75.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t5 ALL idx_b NULL NULL NULL 7 100.00 Using where
1 SIMPLE t7 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t6 ALL NULL NULL NULL NULL 3 100.00 Using where