From 58cd0bd59ef011be54f162237f2ff017c3148e7b Mon Sep 17 00:00:00 2001 From: Igor Babaev Date: Mon, 17 Oct 2022 16:44:10 -0700 Subject: 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 --- mysql-test/main/join_cache.result | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'mysql-test/main/join_cache.result') diff --git a/mysql-test/main/join_cache.result b/mysql-test/main/join_cache.result index 1837576e719..f337ab6509b 100644 --- a/mysql-test/main/join_cache.result +++ b/mysql-test/main/join_cache.result @@ -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 -- cgit v1.2.1