database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-29 05:21:33 +03:00
Code Activity

MDEV-20109: Optimizer ignores distinct key created for materialized...

Browse Source 
(Backported to 10.3, addressed review input)

Sj_materialization_picker::check_qep(): fix error in cost/fanout
calculations:
- for each join prefix, add #prefix_rows / TIME_FOR_COMPARE to the cost,
  like best_extension_by_limited_search does
- Remove the fanout produced by the subquery tables.
- Also take into account join condition selectivity

optimize_wo_join_buffering() (used by LooseScan and FirstMatch)
- also add #prefix_rows / TIME_FOR_COMPARE to the cost of each prefix.
- Also take into account join condition selectivity
This commit is contained in:
Sergei Petrunia
2019-08-29 15:37:49 +03:00
parent d58437d195
commit ef76f81c98
27 changed files with 392 additions and 295 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
mysql-test/main/innodb_ext_key.result
View File

@ -727,8 +727,8 @@ SELECT a FROM t1 AS t, t2
WHERE c = a AND b IN (SELECT b FROM t1, t2 WHERE b = t.b);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t index a,b b 7 NULL 10 Using index
1 PRIMARY t1 ref b b 3 test.t.b 2 Using index
1 PRIMARY t2 index NULL PRIMARY 4 NULL 11 Using index; FirstMatch(t)
1 PRIMARY t1 ref b b 3 test.t.b 2 Using index; Start temporary
1 PRIMARY t2 index NULL PRIMARY 4 NULL 11 Using index; End temporary; Using join buffer (flat, BNL join)
1 PRIMARY t2 eq_ref PRIMARY PRIMARY 4 test.t.a 1 Using index
SELECT a FROM t1 AS t, t2
WHERE c = a AND b IN (SELECT b FROM t1, t2 WHERE b = t.b);
@ -740,8 +740,8 @@ SELECT a FROM t1 AS t, t2
WHERE c = a AND b IN (SELECT b FROM t1, t2 WHERE b = t.b);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t index a,b b 7 NULL 10 Using index
1 PRIMARY t1 ref b b 3 test.t.b 2 Using index
1 PRIMARY t2 index NULL PRIMARY 4 NULL 11 Using index; FirstMatch(t)
1 PRIMARY t1 ref b b 3 test.t.b 2 Using index; Start temporary
1 PRIMARY t2 index NULL PRIMARY 4 NULL 11 Using index; End temporary; Using join buffer (flat, BNL join)
1 PRIMARY t2 eq_ref PRIMARY PRIMARY 4 test.t.a 1 Using index
SELECT a FROM t1 AS t, t2
WHERE c = a AND b IN (SELECT b FROM t1, t2 WHERE b = t.b);