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MDEV-28846 Poor performance when rowid filter contains no elements 
When a range rowid filter was used with an index ref access the cost of
accessing the index entries for the records rejected by the filter was not
taken into account. For a ref access by an index with big average number
of records per key this led to poor execution plans if selectivity of the
used filter was high.
The patch resolves this problem. It also introduces a minor optimization
that skips look-ups into a filter that turns out to be empty.
With this patch the output of ANALYZE stmt reports the number of look-ups
into used rowid filters.
The patch also back-ports from 10.5 the code that properly sets the field
TABLE::file::table for opened temporary tables.

The test cases that were supposed to use rowid filters have been adjusted
in order to use similar execution plans after this fix.

Approved by Oleksandr Byelkin <sanja@mariadb.com>
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@igorbabaev
igorbabaev committed Oct 25, 2022
1 parent f1bbc1c commit 58cd0bd
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Showing 21 changed files with 1,797 additions and 170 deletions.
9 mysql-test/include/rowid_filter_debug_kill.inc
View file
@@ -9,9 +9,6 @@
create table t0(a int);
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);

create table t1(a int);
insert into t1 select A.a + B.a* 10 + C.a * 100 from t0 A, t0 B, t0 C;

# 100 rows
create table t2(a int);
insert into t2 select A.a + B.a* 10 from t0 A, t0 B;
@@ -30,10 +27,10 @@ where table_schema=database() and table_name='t3';
insert into t3
select
A.a,
A.a,
B.a,
'filler-data-filler-data'
from
t0 A, t1 B;
t2 A, t2 B;

analyze table t2,t3;

@@ -63,6 +60,6 @@ disconnect con1;
reap;
set debug_sync='RESET';

drop table t0,t1,t2,t3;
drop table t0,t2,t3;
--source include/wait_until_count_sessions.inc

24 mysql-test/main/join_cache.result
View file
@@ -853,7 +853,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country hash_ALL PRIMARY #hash#PRIMARY 3 world.City.Country 239 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE CountryLanguage hash_ALL|filter PRIMARY,Percentage #hash#PRIMARY|Percentage 3|4 world.City.Country 984 (19%) Using where; Using join buffer (flat, BNLH join); Using rowid filter
1 SIMPLE CountryLanguage hash_ALL PRIMARY,Percentage #hash#PRIMARY 3 world.City.Country 984 Using where; Using join buffer (flat, BNLH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -1053,7 +1053,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country hash_ALL PRIMARY #hash#PRIMARY 3 world.City.Country 239 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE CountryLanguage hash_ALL|filter PRIMARY,Percentage #hash#PRIMARY|Percentage 3|4 world.City.Country 984 (19%) Using where; Using join buffer (incremental, BNLH join); Using rowid filter
1 SIMPLE CountryLanguage hash_ALL PRIMARY,Percentage #hash#PRIMARY 3 world.City.Country 984 Using where; Using join buffer (incremental, BNLH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -1312,7 +1312,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -1509,7 +1509,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -1706,7 +1706,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -1903,7 +1903,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (incremental, BKAH join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (incremental, BKAH join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -2104,7 +2104,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country hash_ALL PRIMARY #hash#PRIMARY 3 world.City.Country 239 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE CountryLanguage hash_ALL|filter PRIMARY,Percentage #hash#PRIMARY|Percentage 3|4 world.City.Country 984 (19%) Using where; Using join buffer (flat, BNLH join); Using rowid filter
1 SIMPLE CountryLanguage hash_ALL PRIMARY,Percentage #hash#PRIMARY 3 world.City.Country 984 Using where; Using join buffer (flat, BNLH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -2208,7 +2208,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country hash_ALL PRIMARY #hash#PRIMARY 3 world.City.Country 239 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE CountryLanguage hash_ALL|filter PRIMARY,Percentage #hash#PRIMARY|Percentage 3|4 world.City.Country 984 (19%) Using where; Using join buffer (incremental, BNLH join); Using rowid filter
1 SIMPLE CountryLanguage hash_ALL PRIMARY,Percentage #hash#PRIMARY 3 world.City.Country 984 Using where; Using join buffer (incremental, BNLH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -2312,7 +2312,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -2416,7 +2416,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -2520,7 +2520,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
@@ -2624,7 +2624,7 @@ LENGTH(Language) < LENGTH(City.Name) - 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City ALL Country NULL NULL NULL 4079 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country 1 Using where; Using join buffer (flat, BKAH join); Key-ordered Rowid-ordered scan
1 SIMPLE CountryLanguage ref|filter PRIMARY,Percentage PRIMARY|Percentage 3|4 world.City.Country 4 (19%) Using index condition(BKA); Using where; Using join buffer (incremental, BKAH join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE CountryLanguage ref PRIMARY,Percentage PRIMARY 3 world.City.Country 4 Using index condition(BKA); Using where; Using join buffer (incremental, BKAH join); Key-ordered Rowid-ordered scan
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
2 mysql-test/main/join_nested_jcl6.result
View file
@@ -2033,7 +2033,7 @@ ON t6.b >= 2 AND t5.b=t7.b AND
(t8.a > 0 OR t8.c IS NULL) AND t6.a>0 AND t7.a>0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t5 ALL NULL NULL NULL NULL 3
1 SIMPLE t7 ref|filter PRIMARY,b_i b_i|PRIMARY 5|4 test.t5.b 2 (29%) Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan; Using rowid filter
1 SIMPLE t7 ref PRIMARY,b_i b_i 5 test.t5.b 2 Using where; Using join buffer (flat, BKA join); Key-ordered Rowid-ordered scan
1 SIMPLE t6 range PRIMARY,b_i PRIMARY 4 NULL 3 Using where; Rowid-ordered scan; Using join buffer (incremental, BNL join)
1 SIMPLE t8 ref b_i b_i 5 test.t5.b 2 Using where; Using join buffer (incremental, BKA join); Key-ordered Rowid-ordered scan
SELECT t5.a,t5.b,t6.a,t6.b,t7.a,t7.b,t8.a,t8.b

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