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MDEV-39942: use actual_rec_per_key in loose scan sj optimization #5284

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MDEV-39942: use actual_rec_per_key in loose scan sj optimization #5284

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4 changes: 2 additions & 2 deletions mysql-test/main/delete_use_source_engines.result
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Original file line number Diff line number Diff line change
Expand Up @@ -3176,7 +3176,7 @@ id select_type table type possible_keys key key_len ref rows Extra
analyze delete from t1 where exists (select 'X' from t1 a where a.c2 = t1.c2)
and c2 >= 3 order by c2;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 PRIMARY a index t1_c2 t1_c2 10 NULL # 16.00 20.00 25.00 Using where; Using index; LooseScan
1 PRIMARY a index t1_c2 t1_c2 10 NULL # 16.00 18.75 25.00 Using where; Using index; LooseScan
1 PRIMARY t1 ref t1_c2 t1_c2 5 test.a.c2 # 5.00 4.76 100.00
select * from t1;
c1 c2 c3
Expand Down Expand Up @@ -5581,7 +5581,7 @@ id select_type table type possible_keys key key_len ref rows Extra
analyze delete from t1 where exists (select 'X' from t1 a where a.c2 = t1.c2)
and c2 >= 3 order by c2;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 PRIMARY a index t1_c2 t1_c2 10 NULL # 16.00 20.00 25.00 Using where; Using index; LooseScan
1 PRIMARY a index t1_c2 t1_c2 10 NULL # 16.00 18.75 25.00 Using where; Using index; LooseScan
1 PRIMARY t1 ref t1_c2 t1_c2 5 test.a.c2 # 5.00 5.00 100.00
select * from t1;
c1 c2 c3
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2 changes: 1 addition & 1 deletion mysql-test/main/opt_hints_join_order.result
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Expand Up @@ -1411,7 +1411,7 @@ WHERE ta4.f1 IN (SELECT /*+ QB_NAME(qb1) */ f1 FROM t4) AND
ta3.f2 IN (SELECT /*+ QB_NAME(qb2) */ f2 FROM t2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 1 100.00
1 PRIMARY t2 index f2 f2 5 NULL 3 100.00 Using where; Using index; LooseScan
1 PRIMARY t2 index f2 f2 5 NULL 3 66.67 Using where; Using index; LooseScan
1 PRIMARY ta3 ref f2 f2 5 test.t2.f2 1 33.33 Using index
1 PRIMARY ta4 index PRIMARY f2 5 NULL 3 100.00 Using index; Using join buffer (flat, BNL join)
1 PRIMARY t4 hash_ALL NULL #hash#$hj 5 test.ta4.f1 1 100.00 Using where; FirstMatch(ta4); Using join buffer (incremental, BNLH join)
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10 changes: 5 additions & 5 deletions mysql-test/main/subselect_sj_mat.result
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Expand Up @@ -107,7 +107,7 @@ a1 a2
explain extended
select * from t1i where a1 in (select b1 from t2i where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2i index it2i1,it2i3 it2i1 # NULL 5 50.00 Using where; Using index; LooseScan
1 PRIMARY t2i index it2i1,it2i3 it2i1 # NULL 5 60.00 Using where; Using index; LooseScan
1 PRIMARY t1i ref _it1_idx _it1_idx # _ref_ 1 20.00
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where `test`.`t1i`.`a1` = `test`.`t2i`.`b1` and `test`.`t2i`.`b1` > '0'
Expand All @@ -130,7 +130,7 @@ a1 a2
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2i index it2i1,it2i2,it2i3 it2i3 # NULL 5 50.00 Using where; Using index; LooseScan
1 PRIMARY t2i index it2i1,it2i2,it2i3 it2i3 # NULL 5 60.00 Using where; Using index; LooseScan
1 PRIMARY t1i ref _it1_idx _it1_idx # _ref_ 1 20.00
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where `test`.`t1i`.`a1` = `test`.`t2i`.`b1` and `test`.`t1i`.`a2` = `test`.`t2i`.`b2` and `test`.`t2i`.`b1` > '0'
Expand Down Expand Up @@ -276,7 +276,7 @@ a1 a2
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 50.00 Using where; Using index; LooseScan
1 PRIMARY t2i index it2i1,it2i2,it2i3 it2i3 18 NULL 5 60.00 Using where; Using index; LooseScan
1 PRIMARY t1i ref it1i1,it1i2,it1i3 it1i3 18 test.t2i.b1,test.t2i.b2 1 20.00 Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` semi join (`test`.`t2i`) where `test`.`t1i`.`a1` = `test`.`t2i`.`b1` and `test`.`t1i`.`a2` = `test`.`t2i`.`b2`
Expand Down Expand Up @@ -348,7 +348,7 @@ where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2i index it2i1,it2i2,it2i3 # # # 5 50.00 #
1 PRIMARY t2i index it2i1,it2i2,it2i3 # # # 5 60.00 #
1 PRIMARY t1i ref it1i1,it1i2,it1i3 # # # 1 20.00 #
1 PRIMARY t3i ref it3i1,it3i2,it3i3 # # # 1 100.00 #
1 PRIMARY t2i ref it2i1,it2i2,it2i3 # # # 1 60.00 #
Expand Down Expand Up @@ -432,7 +432,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t3 ALL NULL # # # 4 15.00 #
4 MATERIALIZED t3 ALL NULL # # # 4 100.00 #
3 MATERIALIZED t3 ALL NULL # # # 4 100.00 #
7 UNION t2i index it2i1,it2i2,it2i3 # # # 5 50.00 #
7 UNION t2i index it2i1,it2i2,it2i3 # # # 5 60.00 #
7 UNION t1i ref it1i1,it1i2,it1i3 # # # 1 20.00 #
7 UNION t3i ref it3i1,it3i2,it3i3 # # # 1 100.00 #
7 UNION t2i ref it2i1,it2i2,it2i3 # # # 1 60.00 #
Expand Down
5 changes: 3 additions & 2 deletions sql/opt_subselect.h
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Expand Up @@ -243,8 +243,9 @@ class Loose_scan_opt
some key components, that may make us think that loose
scan will produce more distinct records than it actually will)
*/
ulong rpc;
if ((rpc= s->table->key_info[key].rec_per_key[max_loose_keypart]))
double rpc=
s->table->key_info[key].actual_rec_per_key(max_loose_keypart);
if (rpc > 0.0) // It's ok to compare like this even if it's double.
records= records / rpc;

// TODO: previous version also did /2
Expand Down