drop table if exists t0,t1,t2,t3; select @@global.use_stat_tables; @@global.use_stat_tables COMPLEMENTARY select @@session.use_stat_tables; @@session.use_stat_tables COMPLEMENTARY set @save_use_stat_tables=@@use_stat_tables; set use_stat_tables='preferably'; set @save_optimizer_use_condition_selectivity=@@optimizer_use_condition_selectivity; set @save_histogram_size=@@histogram_size; set @save_histogram_type=@@histogram_type; set join_cache_level=2; set @@global.histogram_size=0,@@local.histogram_size=0; set histogram_type='single_prec_hb'; set optimizer_use_condition_selectivity=3; create table t1 (a int); insert into t1 values (9), (3), (2), (NULL), (NULL), (2), (NULL), (1), (5), (NULL); analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK select * from mysql.column_stats; db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram test t1 a 1 9 0.4000 4.0000 1.2000 0 NULL NULL flush table t1; explain extended select * from t1 where a is null; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 10 40.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` is null explain extended select * from t1 where a is not null; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 10 60.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` is not null drop table t1; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP DATABASE IF EXISTS dbt3_s001; CREATE DATABASE dbt3_s001; use dbt3_s001; === Q2 === set optimizer_use_condition_selectivity=5; explain extended select s_acctbal, s_name, n_name, p_partkey, p_mfgr, s_address, s_phone, s_comment from part, supplier, partsupp, nation, region where p_partkey = ps_partkey and s_suppkey = ps_suppkey and p_size = 9 and p_type like '%TIN' and s_nationkey = n_nationkey and n_regionkey = r_regionkey and r_name = 'ASIA' and ps_supplycost = ( select min(ps_supplycost) from partsupp, supplier, nation, region where p_partkey = ps_partkey and s_suppkey = ps_suppkey and s_nationkey = n_nationkey and n_regionkey = r_regionkey and r_name = 'ASIA' ) order by s_acctbal desc, n_name, s_name, p_partkey; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 0.31 Using where; Using temporary; Using filesort 1 PRIMARY partsupp ref PRIMARY,i_ps_partkey,i_ps_suppkey i_ps_partkey 4 dbt3_s001.part.p_partkey 3 100.00 Using where 1 PRIMARY supplier eq_ref PRIMARY,i_s_nationkey PRIMARY 4 dbt3_s001.partsupp.ps_suppkey 1 100.00 Using where 1 PRIMARY nation eq_ref PRIMARY,i_n_regionkey PRIMARY 4 dbt3_s001.supplier.s_nationkey 1 100.00 Using where 1 PRIMARY region eq_ref PRIMARY PRIMARY 4 dbt3_s001.nation.n_regionkey 1 20.00 Using where 2 DEPENDENT SUBQUERY region ALL PRIMARY NULL NULL NULL 5 20.00 Using where 2 DEPENDENT SUBQUERY partsupp ref PRIMARY,i_ps_partkey,i_ps_suppkey i_ps_partkey 4 dbt3_s001.part.p_partkey 3 100.00 2 DEPENDENT SUBQUERY supplier eq_ref PRIMARY,i_s_nationkey PRIMARY 4 dbt3_s001.partsupp.ps_suppkey 1 100.00 Using where 2 DEPENDENT SUBQUERY nation eq_ref PRIMARY,i_n_regionkey PRIMARY 4 dbt3_s001.supplier.s_nationkey 1 100.00 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.part.p_partkey' of SELECT #2 was resolved in SELECT #1 Note 1003 /* select#1 */ select `dbt3_s001`.`supplier`.`s_acctbal` AS `s_acctbal`,`dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`nation`.`n_name` AS `n_name`,`dbt3_s001`.`part`.`p_partkey` AS `p_partkey`,`dbt3_s001`.`part`.`p_mfgr` AS `p_mfgr`,`dbt3_s001`.`supplier`.`s_address` AS `s_address`,`dbt3_s001`.`supplier`.`s_phone` AS `s_phone`,`dbt3_s001`.`supplier`.`s_comment` AS `s_comment` from `dbt3_s001`.`part` join `dbt3_s001`.`supplier` join `dbt3_s001`.`partsupp` join `dbt3_s001`.`nation` join `dbt3_s001`.`region` where `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`supplier`.`s_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`part`.`p_size` = 9 and `dbt3_s001`.`nation`.`n_nationkey` = `dbt3_s001`.`supplier`.`s_nationkey` and `dbt3_s001`.`region`.`r_regionkey` = `dbt3_s001`.`nation`.`n_regionkey` and `dbt3_s001`.`region`.`r_name` = 'ASIA' and `dbt3_s001`.`part`.`p_type` like '%TIN' and `dbt3_s001`.`partsupp`.`ps_supplycost` = <`dbt3_s001`.`part`.`p_partkey`>((/* select#2 */ select min(`dbt3_s001`.`partsupp`.`ps_supplycost`) from `dbt3_s001`.`partsupp` join `dbt3_s001`.`supplier` join `dbt3_s001`.`nation` join `dbt3_s001`.`region` where `dbt3_s001`.`supplier`.`s_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`nation`.`n_nationkey` = `dbt3_s001`.`supplier`.`s_nationkey` and `dbt3_s001`.`nation`.`n_regionkey` = `dbt3_s001`.`region`.`r_regionkey` and `dbt3_s001`.`region`.`r_name` = 'ASIA' and `dbt3_s001`.`part`.`p_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey`)) order by `dbt3_s001`.`supplier`.`s_acctbal` desc,`dbt3_s001`.`nation`.`n_name`,`dbt3_s001`.`supplier`.`s_name`,`dbt3_s001`.`part`.`p_partkey` set optimizer_use_condition_selectivity=4; explain extended select s_acctbal, s_name, n_name, p_partkey, p_mfgr, s_address, s_phone, s_comment from part, supplier, partsupp, nation, region where p_partkey = ps_partkey and s_suppkey = ps_suppkey and p_size = 9 and p_type like '%TIN' and s_nationkey = n_nationkey and n_regionkey = r_regionkey and r_name = 'ASIA' and ps_supplycost = ( select min(ps_supplycost) from partsupp, supplier, nation, region where p_partkey = ps_partkey and s_suppkey = ps_suppkey and s_nationkey = n_nationkey and n_regionkey = r_regionkey and r_name = 'ASIA' ) order by s_acctbal desc, n_name, s_name, p_partkey; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY region ALL PRIMARY NULL NULL NULL 5 20.00 Using where; Using temporary; Using filesort 1 PRIMARY nation ref PRIMARY,i_n_regionkey i_n_regionkey 5 dbt3_s001.region.r_regionkey 5 100.00 1 PRIMARY supplier ref PRIMARY,i_s_nationkey i_s_nationkey 5 dbt3_s001.nation.n_nationkey 1 100.00 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 2.08 Using where; Using join buffer (flat, BNL join) 1 PRIMARY partsupp eq_ref PRIMARY,i_ps_partkey,i_ps_suppkey PRIMARY 8 dbt3_s001.part.p_partkey,dbt3_s001.supplier.s_suppkey 1 100.00 Using where 2 DEPENDENT SUBQUERY region ALL PRIMARY NULL NULL NULL 5 20.00 Using where 2 DEPENDENT SUBQUERY partsupp ref PRIMARY,i_ps_partkey,i_ps_suppkey i_ps_partkey 4 dbt3_s001.part.p_partkey 3 100.00 2 DEPENDENT SUBQUERY supplier eq_ref PRIMARY,i_s_nationkey PRIMARY 4 dbt3_s001.partsupp.ps_suppkey 1 100.00 Using where 2 DEPENDENT SUBQUERY nation eq_ref PRIMARY,i_n_regionkey PRIMARY 4 dbt3_s001.supplier.s_nationkey 1 100.00 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.part.p_partkey' of SELECT #2 was resolved in SELECT #1 Note 1003 /* select#1 */ select `dbt3_s001`.`supplier`.`s_acctbal` AS `s_acctbal`,`dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`nation`.`n_name` AS `n_name`,`dbt3_s001`.`part`.`p_partkey` AS `p_partkey`,`dbt3_s001`.`part`.`p_mfgr` AS `p_mfgr`,`dbt3_s001`.`supplier`.`s_address` AS `s_address`,`dbt3_s001`.`supplier`.`s_phone` AS `s_phone`,`dbt3_s001`.`supplier`.`s_comment` AS `s_comment` from `dbt3_s001`.`part` join `dbt3_s001`.`supplier` join `dbt3_s001`.`partsupp` join `dbt3_s001`.`nation` join `dbt3_s001`.`region` where `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`partsupp`.`ps_suppkey` = `dbt3_s001`.`supplier`.`s_suppkey` and `dbt3_s001`.`part`.`p_size` = 9 and `dbt3_s001`.`supplier`.`s_nationkey` = `dbt3_s001`.`nation`.`n_nationkey` and `dbt3_s001`.`nation`.`n_regionkey` = `dbt3_s001`.`region`.`r_regionkey` and `dbt3_s001`.`region`.`r_name` = 'ASIA' and `dbt3_s001`.`part`.`p_type` like '%TIN' and `dbt3_s001`.`partsupp`.`ps_supplycost` = <`dbt3_s001`.`part`.`p_partkey`>((/* select#2 */ select min(`dbt3_s001`.`partsupp`.`ps_supplycost`) from `dbt3_s001`.`partsupp` join `dbt3_s001`.`supplier` join `dbt3_s001`.`nation` join `dbt3_s001`.`region` where `dbt3_s001`.`supplier`.`s_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`nation`.`n_nationkey` = `dbt3_s001`.`supplier`.`s_nationkey` and `dbt3_s001`.`nation`.`n_regionkey` = `dbt3_s001`.`region`.`r_regionkey` and `dbt3_s001`.`region`.`r_name` = 'ASIA' and `dbt3_s001`.`part`.`p_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey`)) order by `dbt3_s001`.`supplier`.`s_acctbal` desc,`dbt3_s001`.`nation`.`n_name`,`dbt3_s001`.`supplier`.`s_name`,`dbt3_s001`.`part`.`p_partkey` === Q15 === create view revenue0 (supplier_no, total_revenue) as select l_suppkey, sum(l_extendedprice * (1 - l_discount)) from lineitem where l_shipdate >= '1995-08-01' and l_shipdate < date_add('1995-08-01', interval 90 day) group by l_suppkey; set @save_optimizer_switch=@@optimizer_switch; set optimizer_switch='index_condition_pushdown=off'; set optimizer_use_condition_selectivity=1; EXPLAIN EXTENDED select s_suppkey, s_name, s_address, s_phone, total_revenue from supplier, revenue0 where s_suppkey = supplier_no and total_revenue = (select max(total_revenue) from revenue0) order by s_suppkey; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY supplier ALL PRIMARY NULL NULL NULL 10 100.00 Using filesort 1 PRIMARY ref key0 key0 5 dbt3_s001.supplier.s_suppkey 10 100.00 Using where 3 DERIVED lineitem range i_l_shipdate,i_l_suppkey i_l_shipdate 4 NULL 269 100.00 Using where; Using temporary; Using filesort 2 SUBQUERY ALL NULL NULL NULL NULL 269 100.00 4 DERIVED lineitem range i_l_shipdate i_l_shipdate 4 NULL 269 100.00 Using where; Using temporary; Using filesort Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`supplier`.`s_suppkey` AS `s_suppkey`,`dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address`,`dbt3_s001`.`supplier`.`s_phone` AS `s_phone`,`revenue0`.`total_revenue` AS `total_revenue` from `dbt3_s001`.`supplier` join `dbt3_s001`.`revenue0` where `revenue0`.`supplier_no` = `dbt3_s001`.`supplier`.`s_suppkey` and `revenue0`.`total_revenue` = (/* select#2 */ select max(`revenue0`.`total_revenue`) from `dbt3_s001`.`revenue0`) order by `dbt3_s001`.`supplier`.`s_suppkey` select s_suppkey, s_name, s_address, s_phone, total_revenue from supplier, revenue0 where s_suppkey = supplier_no and total_revenue = (select max(total_revenue) from revenue0) order by s_suppkey; s_suppkey s_name s_address s_phone total_revenue 1 Supplier#000000001 N kD4on9OM Ipw3,gf0JBoQDd7tgrzrddZ 27-918-335-1736 729084.7773 set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED select s_suppkey, s_name, s_address, s_phone, total_revenue from supplier, revenue0 where s_suppkey = supplier_no and total_revenue = (select max(total_revenue) from revenue0) order by s_suppkey; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY supplier ALL PRIMARY NULL NULL NULL 10 100.00 Using filesort 1 PRIMARY ref key0 key0 5 dbt3_s001.supplier.s_suppkey 10 100.00 Using where 3 DERIVED lineitem range i_l_shipdate,i_l_suppkey i_l_shipdate 4 NULL 269 100.00 Using where; Using temporary; Using filesort 2 SUBQUERY ALL NULL NULL NULL NULL 269 100.00 4 DERIVED lineitem range i_l_shipdate i_l_shipdate 4 NULL 269 100.00 Using where; Using temporary; Using filesort Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`supplier`.`s_suppkey` AS `s_suppkey`,`dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address`,`dbt3_s001`.`supplier`.`s_phone` AS `s_phone`,`revenue0`.`total_revenue` AS `total_revenue` from `dbt3_s001`.`supplier` join `dbt3_s001`.`revenue0` where `revenue0`.`supplier_no` = `dbt3_s001`.`supplier`.`s_suppkey` and `revenue0`.`total_revenue` = (/* select#2 */ select max(`revenue0`.`total_revenue`) from `dbt3_s001`.`revenue0`) order by `dbt3_s001`.`supplier`.`s_suppkey` select s_suppkey, s_name, s_address, s_phone, total_revenue from supplier, revenue0 where s_suppkey = supplier_no and total_revenue = (select max(total_revenue) from revenue0) order by s_suppkey; s_suppkey s_name s_address s_phone total_revenue 1 Supplier#000000001 N kD4on9OM Ipw3,gf0JBoQDd7tgrzrddZ 27-918-335-1736 729084.7773 set optimizer_switch=@save_optimizer_switch; drop view revenue0; === Q16 === set optimizer_use_condition_selectivity=1; EXPLAIN EXTENDED select p_brand, p_type, p_size, count(distinct ps_suppkey) as supplier_cnt from partsupp, part where p_partkey = ps_partkey and p_brand <> 'Brand#11' and p_type not like 'SMALL POLISHED%' and p_size in (49, 37, 27, 5, 40, 6, 22, 8) and ps_suppkey not in (select s_suppkey from supplier where s_comment like '%Customer%Complaints%') group by p_brand, p_type, p_size order by supplier_cnt desc, p_brand, p_type, p_size; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 100.00 Using where; Using temporary; Using filesort 1 PRIMARY partsupp ref PRIMARY,i_ps_partkey PRIMARY 4 dbt3_s001.part.p_partkey 3 100.00 Using where; Using index 2 MATERIALIZED supplier ALL PRIMARY NULL NULL NULL 10 100.00 Using where Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`part`.`p_brand` AS `p_brand`,`dbt3_s001`.`part`.`p_type` AS `p_type`,`dbt3_s001`.`part`.`p_size` AS `p_size`,count(distinct `dbt3_s001`.`partsupp`.`ps_suppkey`) AS `supplier_cnt` from `dbt3_s001`.`partsupp` join `dbt3_s001`.`part` where `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`part`.`p_brand` <> 'Brand#11' and `dbt3_s001`.`part`.`p_type` not like 'SMALL POLISHED%' and `dbt3_s001`.`part`.`p_size` in (49,37,27,5,40,6,22,8) and !<`dbt3_s001`.`partsupp`.`ps_suppkey`>((`dbt3_s001`.`partsupp`.`ps_suppkey`,`dbt3_s001`.`partsupp`.`ps_suppkey` in ( (/* select#2 */ select `dbt3_s001`.`supplier`.`s_suppkey` from `dbt3_s001`.`supplier` where `dbt3_s001`.`supplier`.`s_comment` like '%Customer%Complaints%' ), (`dbt3_s001`.`partsupp`.`ps_suppkey` in on distinct_key where `dbt3_s001`.`partsupp`.`ps_suppkey` = ``.`s_suppkey`)))) group by `dbt3_s001`.`part`.`p_brand`,`dbt3_s001`.`part`.`p_type`,`dbt3_s001`.`part`.`p_size` order by count(distinct `dbt3_s001`.`partsupp`.`ps_suppkey`) desc,`dbt3_s001`.`part`.`p_brand`,`dbt3_s001`.`part`.`p_type`,`dbt3_s001`.`part`.`p_size` select p_brand, p_type, p_size, count(distinct ps_suppkey) as supplier_cnt from partsupp, part where p_partkey = ps_partkey and p_brand <> 'Brand#11' and p_type not like 'SMALL POLISHED%' and p_size in (49, 37, 27, 5, 40, 6, 22, 8) and ps_suppkey not in (select s_suppkey from supplier where s_comment like '%Customer%Complaints%') group by p_brand, p_type, p_size order by supplier_cnt desc, p_brand, p_type, p_size; p_brand p_type p_size supplier_cnt Brand#21 MEDIUM ANODIZED TIN 8 4 Brand#22 PROMO PLATED TIN 5 4 Brand#24 MEDIUM BURNISHED NICKEL 6 4 Brand#24 SMALL ANODIZED STEEL 40 4 Brand#32 MEDIUM BURNISHED BRASS 49 4 Brand#33 MEDIUM POLISHED BRASS 49 4 Brand#41 STANDARD BRUSHED NICKEL 40 4 Brand#44 PROMO POLISHED STEEL 5 4 Brand#45 PROMO ANODIZED BRASS 22 4 Brand#53 STANDARD BRUSHED STEEL 27 4 Brand#54 MEDIUM POLISHED BRASS 22 4 Brand#54 STANDARD ANODIZED BRASS 22 4 Brand#13 LARGE BRUSHED STEEL 8 2 Brand#25 ECONOMY BURNISHED COPPER 27 2 Brand#44 STANDARD PLATED TIN 37 1 Brand#51 ECONOMY POLISHED STEEL 49 1 set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED select p_brand, p_type, p_size, count(distinct ps_suppkey) as supplier_cnt from partsupp, part where p_partkey = ps_partkey and p_brand <> 'Brand#11' and p_type not like 'SMALL POLISHED%' and p_size in (49, 37, 27, 5, 40, 6, 22, 8) and ps_suppkey not in (select s_suppkey from supplier where s_comment like '%Customer%Complaints%') group by p_brand, p_type, p_size order by supplier_cnt desc, p_brand, p_type, p_size; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 16.67 Using where; Using temporary; Using filesort 1 PRIMARY partsupp ref PRIMARY,i_ps_partkey PRIMARY 4 dbt3_s001.part.p_partkey 3 100.00 Using where; Using index 2 MATERIALIZED supplier ALL PRIMARY NULL NULL NULL 10 100.00 Using where Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`part`.`p_brand` AS `p_brand`,`dbt3_s001`.`part`.`p_type` AS `p_type`,`dbt3_s001`.`part`.`p_size` AS `p_size`,count(distinct `dbt3_s001`.`partsupp`.`ps_suppkey`) AS `supplier_cnt` from `dbt3_s001`.`partsupp` join `dbt3_s001`.`part` where `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`part`.`p_brand` <> 'Brand#11' and `dbt3_s001`.`part`.`p_type` not like 'SMALL POLISHED%' and `dbt3_s001`.`part`.`p_size` in (49,37,27,5,40,6,22,8) and !<`dbt3_s001`.`partsupp`.`ps_suppkey`>((`dbt3_s001`.`partsupp`.`ps_suppkey`,`dbt3_s001`.`partsupp`.`ps_suppkey` in ( (/* select#2 */ select `dbt3_s001`.`supplier`.`s_suppkey` from `dbt3_s001`.`supplier` where `dbt3_s001`.`supplier`.`s_comment` like '%Customer%Complaints%' ), (`dbt3_s001`.`partsupp`.`ps_suppkey` in on distinct_key where `dbt3_s001`.`partsupp`.`ps_suppkey` = ``.`s_suppkey`)))) group by `dbt3_s001`.`part`.`p_brand`,`dbt3_s001`.`part`.`p_type`,`dbt3_s001`.`part`.`p_size` order by count(distinct `dbt3_s001`.`partsupp`.`ps_suppkey`) desc,`dbt3_s001`.`part`.`p_brand`,`dbt3_s001`.`part`.`p_type`,`dbt3_s001`.`part`.`p_size` select p_brand, p_type, p_size, count(distinct ps_suppkey) as supplier_cnt from partsupp, part where p_partkey = ps_partkey and p_brand <> 'Brand#11' and p_type not like 'SMALL POLISHED%' and p_size in (49, 37, 27, 5, 40, 6, 22, 8) and ps_suppkey not in (select s_suppkey from supplier where s_comment like '%Customer%Complaints%') group by p_brand, p_type, p_size order by supplier_cnt desc, p_brand, p_type, p_size; p_brand p_type p_size supplier_cnt Brand#21 MEDIUM ANODIZED TIN 8 4 Brand#22 PROMO PLATED TIN 5 4 Brand#24 MEDIUM BURNISHED NICKEL 6 4 Brand#24 SMALL ANODIZED STEEL 40 4 Brand#32 MEDIUM BURNISHED BRASS 49 4 Brand#33 MEDIUM POLISHED BRASS 49 4 Brand#41 STANDARD BRUSHED NICKEL 40 4 Brand#44 PROMO POLISHED STEEL 5 4 Brand#45 PROMO ANODIZED BRASS 22 4 Brand#53 STANDARD BRUSHED STEEL 27 4 Brand#54 MEDIUM POLISHED BRASS 22 4 Brand#54 STANDARD ANODIZED BRASS 22 4 Brand#13 LARGE BRUSHED STEEL 8 2 Brand#25 ECONOMY BURNISHED COPPER 27 2 Brand#44 STANDARD PLATED TIN 37 1 Brand#51 ECONOMY POLISHED STEEL 49 1 set optimizer_use_condition_selectivity=4; EXPLAIN EXTENDED select p_brand, p_type, p_size, count(distinct ps_suppkey) as supplier_cnt from partsupp, part where p_partkey = ps_partkey and p_brand <> 'Brand#11' and p_type not like 'SMALL POLISHED%' and p_size in (49, 37, 27, 5, 40, 6, 22, 8) and ps_suppkey not in (select s_suppkey from supplier where s_comment like '%Customer%Complaints%') group by p_brand, p_type, p_size order by supplier_cnt desc, p_brand, p_type, p_size; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 16.67 Using where; Using temporary; Using filesort 1 PRIMARY partsupp ref PRIMARY,i_ps_partkey PRIMARY 4 dbt3_s001.part.p_partkey 3 100.00 Using where; Using index 2 MATERIALIZED supplier ALL PRIMARY NULL NULL NULL 10 100.00 Using where Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`part`.`p_brand` AS `p_brand`,`dbt3_s001`.`part`.`p_type` AS `p_type`,`dbt3_s001`.`part`.`p_size` AS `p_size`,count(distinct `dbt3_s001`.`partsupp`.`ps_suppkey`) AS `supplier_cnt` from `dbt3_s001`.`partsupp` join `dbt3_s001`.`part` where `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`part`.`p_brand` <> 'Brand#11' and `dbt3_s001`.`part`.`p_type` not like 'SMALL POLISHED%' and `dbt3_s001`.`part`.`p_size` in (49,37,27,5,40,6,22,8) and !<`dbt3_s001`.`partsupp`.`ps_suppkey`>((`dbt3_s001`.`partsupp`.`ps_suppkey`,`dbt3_s001`.`partsupp`.`ps_suppkey` in ( (/* select#2 */ select `dbt3_s001`.`supplier`.`s_suppkey` from `dbt3_s001`.`supplier` where `dbt3_s001`.`supplier`.`s_comment` like '%Customer%Complaints%' ), (`dbt3_s001`.`partsupp`.`ps_suppkey` in on distinct_key where `dbt3_s001`.`partsupp`.`ps_suppkey` = ``.`s_suppkey`)))) group by `dbt3_s001`.`part`.`p_brand`,`dbt3_s001`.`part`.`p_type`,`dbt3_s001`.`part`.`p_size` order by count(distinct `dbt3_s001`.`partsupp`.`ps_suppkey`) desc,`dbt3_s001`.`part`.`p_brand`,`dbt3_s001`.`part`.`p_type`,`dbt3_s001`.`part`.`p_size` select p_brand, p_type, p_size, count(distinct ps_suppkey) as supplier_cnt from partsupp, part where p_partkey = ps_partkey and p_brand <> 'Brand#11' and p_type not like 'SMALL POLISHED%' and p_size in (49, 37, 27, 5, 40, 6, 22, 8) and ps_suppkey not in (select s_suppkey from supplier where s_comment like '%Customer%Complaints%') group by p_brand, p_type, p_size order by supplier_cnt desc, p_brand, p_type, p_size; p_brand p_type p_size supplier_cnt Brand#21 MEDIUM ANODIZED TIN 8 4 Brand#22 PROMO PLATED TIN 5 4 Brand#24 MEDIUM BURNISHED NICKEL 6 4 Brand#24 SMALL ANODIZED STEEL 40 4 Brand#32 MEDIUM BURNISHED BRASS 49 4 Brand#33 MEDIUM POLISHED BRASS 49 4 Brand#41 STANDARD BRUSHED NICKEL 40 4 Brand#44 PROMO POLISHED STEEL 5 4 Brand#45 PROMO ANODIZED BRASS 22 4 Brand#53 STANDARD BRUSHED STEEL 27 4 Brand#54 MEDIUM POLISHED BRASS 22 4 Brand#54 STANDARD ANODIZED BRASS 22 4 Brand#13 LARGE BRUSHED STEEL 8 2 Brand#25 ECONOMY BURNISHED COPPER 27 2 Brand#44 STANDARD PLATED TIN 37 1 Brand#51 ECONOMY POLISHED STEEL 49 1 === Q18 === set optimizer_use_condition_selectivity=1; EXPLAIN EXTENDED select c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice, sum(l_quantity) from customer, orders, lineitem where o_orderkey in (select l_orderkey from lineitem group by l_orderkey having sum(l_quantity) > 250) and c_custkey = o_custkey and o_orderkey = l_orderkey group by c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice order by o_totalprice desc, o_orderdate; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY orders ALL PRIMARY,i_o_custkey NULL NULL NULL 1500 100.00 Using where; Using temporary; Using filesort 1 PRIMARY eq_ref distinct_key distinct_key 4 dbt3_s001.orders.o_orderkey 1 100.00 1 PRIMARY customer eq_ref PRIMARY PRIMARY 4 dbt3_s001.orders.o_custkey 1 100.00 1 PRIMARY lineitem ref PRIMARY,i_l_orderkey,i_l_orderkey_quantity i_l_orderkey_quantity 4 dbt3_s001.orders.o_orderkey 4 100.00 Using index 2 MATERIALIZED lineitem index NULL i_l_orderkey_quantity 13 NULL 6005 100.00 Using index Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`customer`.`c_name` AS `c_name`,`dbt3_s001`.`customer`.`c_custkey` AS `c_custkey`,`dbt3_s001`.`orders`.`o_orderkey` AS `o_orderkey`,`dbt3_s001`.`orders`.`o_orderDATE` AS `o_orderdate`,`dbt3_s001`.`orders`.`o_totalprice` AS `o_totalprice`,sum(`dbt3_s001`.`lineitem`.`l_quantity`) AS `sum(l_quantity)` from (/* select#2 */ select `dbt3_s001`.`lineitem`.`l_orderkey` from `dbt3_s001`.`lineitem` group by `dbt3_s001`.`lineitem`.`l_orderkey` having sum(`dbt3_s001`.`lineitem`.`l_quantity`) > 250) join `dbt3_s001`.`customer` join `dbt3_s001`.`orders` join `dbt3_s001`.`lineitem` where `dbt3_s001`.`customer`.`c_custkey` = `dbt3_s001`.`orders`.`o_custkey` and ``.`l_orderkey` = `dbt3_s001`.`orders`.`o_orderkey` and `dbt3_s001`.`lineitem`.`l_orderkey` = `dbt3_s001`.`orders`.`o_orderkey` group by `dbt3_s001`.`customer`.`c_name`,`dbt3_s001`.`customer`.`c_custkey`,`dbt3_s001`.`orders`.`o_orderkey`,`dbt3_s001`.`orders`.`o_orderDATE`,`dbt3_s001`.`orders`.`o_totalprice` order by `dbt3_s001`.`orders`.`o_totalprice` desc,`dbt3_s001`.`orders`.`o_orderDATE` select c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice, sum(l_quantity) from customer, orders, lineitem where o_orderkey in (select l_orderkey from lineitem group by l_orderkey having sum(l_quantity) > 250) and c_custkey = o_custkey and o_orderkey = l_orderkey group by c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice order by o_totalprice desc, o_orderdate; c_name c_custkey o_orderkey o_orderdate o_totalprice sum(l_quantity) Customer#000000070 70 2567 1998-02-27 263411.29 266 Customer#000000010 10 4421 1997-04-04 258779.02 255 Customer#000000082 82 3460 1995-10-03 245976.74 254 Customer#000000068 68 2208 1995-05-01 245388.06 256 set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED select c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice, sum(l_quantity) from customer, orders, lineitem where o_orderkey in (select l_orderkey from lineitem group by l_orderkey having sum(l_quantity) > 250) and c_custkey = o_custkey and o_orderkey = l_orderkey group by c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice order by o_totalprice desc, o_orderdate; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY orders ALL PRIMARY,i_o_custkey NULL NULL NULL 1500 100.00 Using where; Using temporary; Using filesort 1 PRIMARY eq_ref distinct_key distinct_key 4 dbt3_s001.orders.o_orderkey 1 100.00 1 PRIMARY customer eq_ref PRIMARY PRIMARY 4 dbt3_s001.orders.o_custkey 1 100.00 1 PRIMARY lineitem ref PRIMARY,i_l_orderkey,i_l_orderkey_quantity i_l_orderkey_quantity 4 dbt3_s001.orders.o_orderkey 4 100.00 Using index 2 MATERIALIZED lineitem index NULL i_l_orderkey_quantity 13 NULL 6005 100.00 Using index Warnings: Note 1003 /* select#1 */ select `dbt3_s001`.`customer`.`c_name` AS `c_name`,`dbt3_s001`.`customer`.`c_custkey` AS `c_custkey`,`dbt3_s001`.`orders`.`o_orderkey` AS `o_orderkey`,`dbt3_s001`.`orders`.`o_orderDATE` AS `o_orderdate`,`dbt3_s001`.`orders`.`o_totalprice` AS `o_totalprice`,sum(`dbt3_s001`.`lineitem`.`l_quantity`) AS `sum(l_quantity)` from (/* select#2 */ select `dbt3_s001`.`lineitem`.`l_orderkey` from `dbt3_s001`.`lineitem` group by `dbt3_s001`.`lineitem`.`l_orderkey` having sum(`dbt3_s001`.`lineitem`.`l_quantity`) > 250) join `dbt3_s001`.`customer` join `dbt3_s001`.`orders` join `dbt3_s001`.`lineitem` where `dbt3_s001`.`customer`.`c_custkey` = `dbt3_s001`.`orders`.`o_custkey` and ``.`l_orderkey` = `dbt3_s001`.`orders`.`o_orderkey` and `dbt3_s001`.`lineitem`.`l_orderkey` = `dbt3_s001`.`orders`.`o_orderkey` group by `dbt3_s001`.`customer`.`c_name`,`dbt3_s001`.`customer`.`c_custkey`,`dbt3_s001`.`orders`.`o_orderkey`,`dbt3_s001`.`orders`.`o_orderDATE`,`dbt3_s001`.`orders`.`o_totalprice` order by `dbt3_s001`.`orders`.`o_totalprice` desc,`dbt3_s001`.`orders`.`o_orderDATE` select c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice, sum(l_quantity) from customer, orders, lineitem where o_orderkey in (select l_orderkey from lineitem group by l_orderkey having sum(l_quantity) > 250) and c_custkey = o_custkey and o_orderkey = l_orderkey group by c_name, c_custkey, o_orderkey, o_orderdate, o_totalprice order by o_totalprice desc, o_orderdate; c_name c_custkey o_orderkey o_orderdate o_totalprice sum(l_quantity) Customer#000000070 70 2567 1998-02-27 263411.29 266 Customer#000000010 10 4421 1997-04-04 258779.02 255 Customer#000000082 82 3460 1995-10-03 245976.74 254 Customer#000000068 68 2208 1995-05-01 245388.06 256 === Q22 === set optimizer_use_condition_selectivity=1; EXPLAIN EXTENDED select cntrycode, count(*) as numcust, sum(c_acctbal) as totacctbal from ( select substr(c_phone, 1, 2) as cntrycode, c_acctbal from customer where substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25') and c_acctbal > (select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25')) and not exists (select * from orders where o_custkey = c_custkey) ) as vip group by cntrycode order by cntrycode; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY customer ALL NULL NULL NULL NULL 150 100.00 Using where; Using temporary; Using filesort 4 DEPENDENT SUBQUERY orders ref i_o_custkey i_o_custkey 5 dbt3_s001.customer.c_custkey 15 100.00 Using index 3 SUBQUERY customer ALL NULL NULL NULL NULL 150 100.00 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.customer.c_custkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select substr(`dbt3_s001`.`customer`.`c_phone`,1,2) AS `cntrycode`,count(0) AS `numcust`,sum(`dbt3_s001`.`customer`.`c_acctbal`) AS `totacctbal` from `dbt3_s001`.`customer` where substr(`dbt3_s001`.`customer`.`c_phone`,1,2) in ('10','20','14','19','11','28','25') and `dbt3_s001`.`customer`.`c_acctbal` > (/* select#3 */ select avg(`dbt3_s001`.`customer`.`c_acctbal`) from `dbt3_s001`.`customer` where `dbt3_s001`.`customer`.`c_acctbal` > 0.00 and substr(`dbt3_s001`.`customer`.`c_phone`,1,2) in ('10','20','14','19','11','28','25')) and !(1,<`dbt3_s001`.`customer`.`c_custkey`>(exists(/* select#4 */ select 1 from `dbt3_s001`.`orders` where `dbt3_s001`.`orders`.`o_custkey` = `dbt3_s001`.`customer`.`c_custkey` limit 1))) group by substr(`dbt3_s001`.`customer`.`c_phone`,1,2) order by substr(`dbt3_s001`.`customer`.`c_phone`,1,2) select cntrycode, count(*) as numcust, sum(c_acctbal) as totacctbal from ( select substr(c_phone, 1, 2) as cntrycode, c_acctbal from customer where substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25') and c_acctbal > (select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25')) and not exists (select * from orders where o_custkey = c_custkey) ) as vip group by cntrycode order by cntrycode; cntrycode numcust totacctbal 11 4 29942.58 19 2 17120.35 20 1 9091.82 28 2 14755.5 set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED select cntrycode, count(*) as numcust, sum(c_acctbal) as totacctbal from ( select substr(c_phone, 1, 2) as cntrycode, c_acctbal from customer where substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25') and c_acctbal > (select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25')) and not exists (select * from orders where o_custkey = c_custkey) ) as vip group by cntrycode order by cntrycode; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY customer ALL NULL NULL NULL NULL 150 100.00 Using where; Using temporary; Using filesort 4 DEPENDENT SUBQUERY orders ref i_o_custkey i_o_custkey 5 dbt3_s001.customer.c_custkey 15 100.00 Using index 3 SUBQUERY customer ALL NULL NULL NULL NULL 150 91.00 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.customer.c_custkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select substr(`dbt3_s001`.`customer`.`c_phone`,1,2) AS `cntrycode`,count(0) AS `numcust`,sum(`dbt3_s001`.`customer`.`c_acctbal`) AS `totacctbal` from `dbt3_s001`.`customer` where substr(`dbt3_s001`.`customer`.`c_phone`,1,2) in ('10','20','14','19','11','28','25') and `dbt3_s001`.`customer`.`c_acctbal` > (/* select#3 */ select avg(`dbt3_s001`.`customer`.`c_acctbal`) from `dbt3_s001`.`customer` where `dbt3_s001`.`customer`.`c_acctbal` > 0.00 and substr(`dbt3_s001`.`customer`.`c_phone`,1,2) in ('10','20','14','19','11','28','25')) and !(1,<`dbt3_s001`.`customer`.`c_custkey`>(exists(/* select#4 */ select 1 from `dbt3_s001`.`orders` where `dbt3_s001`.`orders`.`o_custkey` = `dbt3_s001`.`customer`.`c_custkey` limit 1))) group by substr(`dbt3_s001`.`customer`.`c_phone`,1,2) order by substr(`dbt3_s001`.`customer`.`c_phone`,1,2) select cntrycode, count(*) as numcust, sum(c_acctbal) as totacctbal from ( select substr(c_phone, 1, 2) as cntrycode, c_acctbal from customer where substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25') and c_acctbal > (select avg(c_acctbal) from customer where c_acctbal > 0.00 and substr(c_phone, 1, 2) in ('10', '20', '14', '19', '11', '28', '25')) and not exists (select * from orders where o_custkey = c_custkey) ) as vip group by cntrycode order by cntrycode; cntrycode numcust totacctbal 11 4 29942.58 19 2 17120.35 20 1 9091.82 28 2 14755.5 === Q20 === set optimizer_use_condition_selectivity=1; EXPLAIN EXTENDED select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY supplier ALL PRIMARY,i_s_nationkey NULL NULL NULL 10 100.00 Using where; Using filesort 1 PRIMARY eq_ref distinct_key distinct_key 4 func 1 100.00 1 PRIMARY nation eq_ref PRIMARY PRIMARY 4 dbt3_s001.supplier.s_nationkey 1 100.00 Using where 2 MATERIALIZED part ALL PRIMARY NULL NULL NULL 200 100.00 Using where 2 MATERIALIZED partsupp ref PRIMARY,i_ps_partkey,i_ps_suppkey i_ps_partkey 4 dbt3_s001.part.p_partkey 3 100.00 Using where 4 DEPENDENT SUBQUERY lineitem ref i_l_shipdate,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey i_l_suppkey_partkey 10 dbt3_s001.partsupp.ps_partkey,dbt3_s001.partsupp.ps_suppkey 8 100.00 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.partsupp.ps_partkey' of SELECT #4 was resolved in SELECT #2 Note 1276 Field or reference 'dbt3_s001.partsupp.ps_suppkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select sql_calc_found_rows `dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address` from `dbt3_s001`.`supplier` semi join (`dbt3_s001`.`part` join `dbt3_s001`.`partsupp`) join `dbt3_s001`.`nation` where `dbt3_s001`.`nation`.`n_nationkey` = `dbt3_s001`.`supplier`.`s_nationkey` and `dbt3_s001`.`nation`.`n_name` = 'UNITED STATES' and `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`partsupp`.`ps_availqty` > <`dbt3_s001`.`partsupp`.`ps_partkey`,`dbt3_s001`.`partsupp`.`ps_suppkey`>((/* select#4 */ select 0.5 * sum(`dbt3_s001`.`lineitem`.`l_quantity`) from `dbt3_s001`.`lineitem` where `dbt3_s001`.`lineitem`.`l_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey` and `dbt3_s001`.`lineitem`.`l_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`lineitem`.`l_shipDATE` >= (cast('1993-01-01' as date)) and `dbt3_s001`.`lineitem`.`l_shipDATE` < (cast('1993-01-01' as date) + interval '1' year))) and `dbt3_s001`.`part`.`p_name` like 'g%' order by `dbt3_s001`.`supplier`.`s_name` limit 10 select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; s_name s_address Supplier#000000010 Saygah3gYWMp72i PY SELECT ((SELECT COUNT(*) FROM part WHERE p_name LIKE 'g%') / (SELECT COUNT(*) FROM part)) AS sel; sel 0.0600 set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY nation ALL PRIMARY NULL NULL NULL 25 4.00 Using where; Using temporary; Using filesort 1 PRIMARY supplier ref PRIMARY,i_s_nationkey i_s_nationkey 5 dbt3_s001.nation.n_nationkey 1 100.00 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 4.17 Using where; Start temporary; Using join buffer (flat, BNL join) 1 PRIMARY partsupp eq_ref PRIMARY,i_ps_partkey,i_ps_suppkey PRIMARY 8 dbt3_s001.part.p_partkey,dbt3_s001.supplier.s_suppkey 1 100.00 Using where; End temporary 4 DEPENDENT SUBQUERY lineitem ref i_l_shipdate,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey i_l_suppkey_partkey 10 dbt3_s001.partsupp.ps_partkey,dbt3_s001.partsupp.ps_suppkey 8 15.14 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.partsupp.ps_partkey' of SELECT #4 was resolved in SELECT #2 Note 1276 Field or reference 'dbt3_s001.partsupp.ps_suppkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select sql_calc_found_rows `dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address` from `dbt3_s001`.`supplier` semi join (`dbt3_s001`.`part` join `dbt3_s001`.`partsupp`) join `dbt3_s001`.`nation` where `dbt3_s001`.`supplier`.`s_nationkey` = `dbt3_s001`.`nation`.`n_nationkey` and `dbt3_s001`.`nation`.`n_name` = 'UNITED STATES' and `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`partsupp`.`ps_suppkey` = `dbt3_s001`.`supplier`.`s_suppkey` and `dbt3_s001`.`partsupp`.`ps_availqty` > <`dbt3_s001`.`partsupp`.`ps_partkey`,`dbt3_s001`.`partsupp`.`ps_suppkey`>((/* select#4 */ select 0.5 * sum(`dbt3_s001`.`lineitem`.`l_quantity`) from `dbt3_s001`.`lineitem` where `dbt3_s001`.`lineitem`.`l_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey` and `dbt3_s001`.`lineitem`.`l_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`lineitem`.`l_shipDATE` >= (cast('1993-01-01' as date)) and `dbt3_s001`.`lineitem`.`l_shipDATE` < (cast('1993-01-01' as date) + interval '1' year))) and `dbt3_s001`.`part`.`p_name` like 'g%' order by `dbt3_s001`.`supplier`.`s_name` limit 10 select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; s_name s_address Supplier#000000010 Saygah3gYWMp72i PY set histogram_size=127; ANALYZE TABLE part PERSISTENT FOR COLUMNS(p_name) INDEXES(); Table Op Msg_type Msg_text dbt3_s001.part analyze status Engine-independent statistics collected dbt3_s001.part analyze status Table is already up to date flush table part; set optimizer_use_condition_selectivity=4; EXPLAIN EXTENDED select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY nation ALL PRIMARY NULL NULL NULL 25 4.00 Using where; Using temporary; Using filesort 1 PRIMARY supplier ref PRIMARY,i_s_nationkey i_s_nationkey 5 dbt3_s001.nation.n_nationkey 1 100.00 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 7.03 Using where 1 PRIMARY partsupp eq_ref PRIMARY,i_ps_partkey,i_ps_suppkey PRIMARY 8 dbt3_s001.part.p_partkey,dbt3_s001.supplier.s_suppkey 1 100.00 Using where; FirstMatch(supplier) 4 DEPENDENT SUBQUERY lineitem ref i_l_shipdate,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey i_l_suppkey_partkey 10 dbt3_s001.partsupp.ps_partkey,dbt3_s001.partsupp.ps_suppkey 8 15.14 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.partsupp.ps_partkey' of SELECT #4 was resolved in SELECT #2 Note 1276 Field or reference 'dbt3_s001.partsupp.ps_suppkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select sql_calc_found_rows `dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address` from `dbt3_s001`.`supplier` semi join (`dbt3_s001`.`part` join `dbt3_s001`.`partsupp`) join `dbt3_s001`.`nation` where `dbt3_s001`.`supplier`.`s_nationkey` = `dbt3_s001`.`nation`.`n_nationkey` and `dbt3_s001`.`nation`.`n_name` = 'UNITED STATES' and `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`partsupp`.`ps_suppkey` = `dbt3_s001`.`supplier`.`s_suppkey` and `dbt3_s001`.`partsupp`.`ps_availqty` > <`dbt3_s001`.`partsupp`.`ps_partkey`,`dbt3_s001`.`partsupp`.`ps_suppkey`>((/* select#4 */ select 0.5 * sum(`dbt3_s001`.`lineitem`.`l_quantity`) from `dbt3_s001`.`lineitem` where `dbt3_s001`.`lineitem`.`l_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey` and `dbt3_s001`.`lineitem`.`l_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`lineitem`.`l_shipDATE` >= (cast('1993-01-01' as date)) and `dbt3_s001`.`lineitem`.`l_shipDATE` < (cast('1993-01-01' as date) + interval '1' year))) and `dbt3_s001`.`part`.`p_name` like 'g%' order by `dbt3_s001`.`supplier`.`s_name` limit 10 select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; s_name s_address Supplier#000000010 Saygah3gYWMp72i PY set histogram_type='DOUBLE_PREC_HB'; set histogram_size=126; ANALYZE TABLE part PERSISTENT FOR COLUMNS(p_name) INDEXES(); Table Op Msg_type Msg_text dbt3_s001.part analyze status Engine-independent statistics collected dbt3_s001.part analyze status Table is already up to date flush table part; EXPLAIN EXTENDED select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY nation ALL PRIMARY NULL NULL NULL 25 4.00 Using where; Using temporary; Using filesort 1 PRIMARY supplier ref PRIMARY,i_s_nationkey i_s_nationkey 5 dbt3_s001.nation.n_nationkey 1 100.00 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 7.81 Using where 1 PRIMARY partsupp eq_ref PRIMARY,i_ps_partkey,i_ps_suppkey PRIMARY 8 dbt3_s001.part.p_partkey,dbt3_s001.supplier.s_suppkey 1 100.00 Using where; FirstMatch(supplier) 4 DEPENDENT SUBQUERY lineitem ref i_l_shipdate,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey i_l_suppkey_partkey 10 dbt3_s001.partsupp.ps_partkey,dbt3_s001.partsupp.ps_suppkey 8 15.14 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.partsupp.ps_partkey' of SELECT #4 was resolved in SELECT #2 Note 1276 Field or reference 'dbt3_s001.partsupp.ps_suppkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select sql_calc_found_rows `dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address` from `dbt3_s001`.`supplier` semi join (`dbt3_s001`.`part` join `dbt3_s001`.`partsupp`) join `dbt3_s001`.`nation` where `dbt3_s001`.`supplier`.`s_nationkey` = `dbt3_s001`.`nation`.`n_nationkey` and `dbt3_s001`.`nation`.`n_name` = 'UNITED STATES' and `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`partsupp`.`ps_suppkey` = `dbt3_s001`.`supplier`.`s_suppkey` and `dbt3_s001`.`partsupp`.`ps_availqty` > <`dbt3_s001`.`partsupp`.`ps_partkey`,`dbt3_s001`.`partsupp`.`ps_suppkey`>((/* select#4 */ select 0.5 * sum(`dbt3_s001`.`lineitem`.`l_quantity`) from `dbt3_s001`.`lineitem` where `dbt3_s001`.`lineitem`.`l_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey` and `dbt3_s001`.`lineitem`.`l_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`lineitem`.`l_shipDATE` >= (cast('1993-01-01' as date)) and `dbt3_s001`.`lineitem`.`l_shipDATE` < (cast('1993-01-01' as date) + interval '1' year))) and `dbt3_s001`.`part`.`p_name` like 'g%' order by `dbt3_s001`.`supplier`.`s_name` limit 10 select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; s_name s_address Supplier#000000010 Saygah3gYWMp72i PY set histogram_type='SINGLE_PREC_HB'; set histogram_size=24; ANALYZE TABLE nation PERSISTENT FOR COLUMNS(n_name) INDEXES(); Table Op Msg_type Msg_text dbt3_s001.nation analyze status Engine-independent statistics collected dbt3_s001.nation analyze status Table is already up to date flush table nation; EXPLAIN EXTENDED select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY nation ALL PRIMARY NULL NULL NULL 25 4.00 Using where; Using temporary; Using filesort 1 PRIMARY supplier ref PRIMARY,i_s_nationkey i_s_nationkey 5 dbt3_s001.nation.n_nationkey 1 100.00 1 PRIMARY part ALL PRIMARY NULL NULL NULL 200 7.81 Using where 1 PRIMARY partsupp eq_ref PRIMARY,i_ps_partkey,i_ps_suppkey PRIMARY 8 dbt3_s001.part.p_partkey,dbt3_s001.supplier.s_suppkey 1 100.00 Using where; FirstMatch(supplier) 4 DEPENDENT SUBQUERY lineitem ref i_l_shipdate,i_l_suppkey_partkey,i_l_partkey,i_l_suppkey i_l_suppkey_partkey 10 dbt3_s001.partsupp.ps_partkey,dbt3_s001.partsupp.ps_suppkey 8 15.14 Using where Warnings: Note 1276 Field or reference 'dbt3_s001.partsupp.ps_partkey' of SELECT #4 was resolved in SELECT #2 Note 1276 Field or reference 'dbt3_s001.partsupp.ps_suppkey' of SELECT #4 was resolved in SELECT #2 Note 1003 /* select#1 */ select sql_calc_found_rows `dbt3_s001`.`supplier`.`s_name` AS `s_name`,`dbt3_s001`.`supplier`.`s_address` AS `s_address` from `dbt3_s001`.`supplier` semi join (`dbt3_s001`.`part` join `dbt3_s001`.`partsupp`) join `dbt3_s001`.`nation` where `dbt3_s001`.`supplier`.`s_nationkey` = `dbt3_s001`.`nation`.`n_nationkey` and `dbt3_s001`.`nation`.`n_name` = 'UNITED STATES' and `dbt3_s001`.`partsupp`.`ps_partkey` = `dbt3_s001`.`part`.`p_partkey` and `dbt3_s001`.`partsupp`.`ps_suppkey` = `dbt3_s001`.`supplier`.`s_suppkey` and `dbt3_s001`.`partsupp`.`ps_availqty` > <`dbt3_s001`.`partsupp`.`ps_partkey`,`dbt3_s001`.`partsupp`.`ps_suppkey`>((/* select#4 */ select 0.5 * sum(`dbt3_s001`.`lineitem`.`l_quantity`) from `dbt3_s001`.`lineitem` where `dbt3_s001`.`lineitem`.`l_partkey` = `dbt3_s001`.`partsupp`.`ps_partkey` and `dbt3_s001`.`lineitem`.`l_suppkey` = `dbt3_s001`.`partsupp`.`ps_suppkey` and `dbt3_s001`.`lineitem`.`l_shipDATE` >= (cast('1993-01-01' as date)) and `dbt3_s001`.`lineitem`.`l_shipDATE` < (cast('1993-01-01' as date) + interval '1' year))) and `dbt3_s001`.`part`.`p_name` like 'g%' order by `dbt3_s001`.`supplier`.`s_name` limit 10 select sql_calc_found_rows s_name, s_address from supplier, nation where s_suppkey in (select ps_suppkey from partsupp where ps_partkey in (select p_partkey from part where p_name like 'g%') and ps_availqty > (select 0.5 * sum(l_quantity) from lineitem where l_partkey = ps_partkey and l_suppkey = ps_suppkey and l_shipdate >= date('1993-01-01') and l_shipdate < date('1993-01-01') + interval '1' year )) and s_nationkey = n_nationkey and n_name = 'UNITED STATES' order by s_name limit 10; s_name s_address Supplier#000000010 Saygah3gYWMp72i PY DROP DATABASE dbt3_s001; set histogram_type=@save_histogram_type; set histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; use test; # # Bug mdev-4348: using view with use_condition_selectivity > 1 # set @tmp_use_stat_tables=@@use_stat_tables; set use_stat_tables='never'; set optimizer_use_condition_selectivity=3; CREATE TABLE t1 (a int, b int); INSERT t1 VALUES (7,1), (0,7); CREATE ALGORITHM=MERGE VIEW v1 AS SELECT * FROM t1; CREATE TABLE t2 (c int, d int, index idx(d)); INSERT INTO t2 VALUES (0,4), (8,6), (1,3), (8,5), (9,3), (2,2), (6,2), (1,9), (6,3), (2,8), (4,1), (0,7), (4,8), (4,5); EXPLAIN EXTENDED SELECT * FROM v1 INNER JOIN t2 ON ( a = c AND b = d ); id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using where 1 SIMPLE t2 ref idx idx 5 test.t1.b 2 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d` from `test`.`t1` join `test`.`t2` where `test`.`t2`.`c` = `test`.`t1`.`a` and `test`.`t2`.`d` = `test`.`t1`.`b` SELECT * FROM v1 INNER JOIN t2 ON ( a = c AND b = d ); a b c d 0 7 0 7 DROP VIEW v1; DROP TABLE t1,t2; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; set use_stat_tables=@tmp_use_stat_tables; # # Bug mdev-4349: impossible range for non-indexed column # set optimizer_use_condition_selectivity=3; create table t1 (a int); insert into t1 values (3), (7), (2), (5), (7), (1), (2), (2); set optimizer_use_condition_selectivity=1; explain extended select * from t1 where a < 1 and a > 7; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 8 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` < 1 and `test`.`t1`.`a` > 7 select * from t1 where a < 1 and a > 7; a set optimizer_use_condition_selectivity=3; explain extended select * from t1 where a < 1 and a > 7; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 8 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` < 1 and `test`.`t1`.`a` > 7 select * from t1 where a < 1 and a > 7; a drop table t1; create table t1 (a int); insert into t1 values (1); create table t2 (b int); insert into t2 values (2),(3); explain extended select * from t1 where a in ( select b from t2 ) AND ( a > 3 ); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1003 select 1 AS `a` from (`test`.`t2`) where 0 select * from t1 where a in ( select b from t2 ) AND ( a > 3 ); a drop table t1,t2; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # Bug mdev-4350: erroneous negative selectivity # create table t1 (a int); insert into t1 values (1), (1); insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 select * from t1; insert into t1 values (0); select count(*) from t1; count(*) 1025 set use_stat_tables='preferably'; set histogram_size=127; set histogram_type='SINGLE_PREC_HB'; analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK flush table t1; set optimizer_use_condition_selectivity=4; explain extended select * from t1 where a=0; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 1025 0.39 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` = 0 drop table t1; set histogram_size=@save_histogram_size; set histogram_type=@save_histogram_type; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # Bug mdev-4367: 2-way join with an empty table # when optimizer_use_condition_selectivity=3 # set optimizer_use_condition_selectivity=3; CREATE TABLE t1 (a varchar(1)) ENGINE=MyISAM; INSERT INTO t1 VALUES ('j'),('k'); CREATE TABLE t2 (b varchar(1)) ENGINE=MyISAM; INSERT INTO t2 VALUES ('x'),('y'); CREATE TABLE t3 (c varchar(1), KEY(c)) ENGINE=MyISAM; SELECT * FROM t1 STRAIGHT_JOIN (t2 JOIN t3 ON c = b AND b > 'z'); a b c DROP TABLE t1,t2,t3; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # Bug mdev-4366: impossible condition on an indexed column discovered after # substitution of constant tables # with optimizer_use_condition_selectivity=3 # CREATE TABLE t1 (pk int PRIMARY KEY, a int); INSERT INTO t1 VALUES (1,4), (2,6), (3,3), (4,5); CREATE TABLE t2 (b int); INSERT INTO t2 VALUES (1), (7); set optimizer_use_condition_selectivity=1; EXPLAIN EXTENDED SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1003 select 1 AS `1` from `test`.`t1` join `test`.`t2` where 0 SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10; 1 set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1003 select 1 AS `1` from `test`.`t1` join `test`.`t2` where 0 SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10; 1 DROP TABLE t1,t2; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # Bug mdev-4370: Histograms have bean created, but the query is run after # FLUSH TABLES with optimizer_use_condition_selectivity=3 # set use_stat_tables=PREFERABLY; set histogram_size=10; set histogram_type='SINGLE_PREC_HB'; CREATE TABLE t1 (a int); INSERT INTO t1 VALUES (9), (1); ANALYZE TABLE t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK FLUSH TABLES; set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED SELECT * FROM t1 WHERE a > 3; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 2 75.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 3 SELECT * FROM t1 WHERE a > 3; a 9 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1; set histogram_size=@save_histogram_size; set histogram_type=@save_histogram_type; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4371: Join with condition supported by index on an empty table # with optimizer_use_condition_selectivity=3 # set use_stat_tables=PREFERABLY; CREATE TABLE t1 (a int, b int, INDEX(a)); CREATE TABLE t2 (c int); INSERT INTO t2 VALUES (1),(2),(3),(4),(5),(6),(7),(8); ANALYZE TABLE t1, t2; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status Table is already up to date test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK FLUSH TABLES; set optimizer_use_condition_selectivity=3; set @save_optimizer_switch=@@optimizer_switch; set optimizer_switch='index_condition_pushdown=off'; EXPLAIN EXTENDED SELECT * FROM t1, t2 WHERE a > 9; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1003 select NULL AS `a`,NULL AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where 0 SELECT * FROM t1, t2 WHERE a > 9; a b c set optimizer_switch=@save_optimizer_switch; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4373: condition on a short varchar column # with optimizer_use_condition_selectivity=3 # set use_stat_tables=PREFERABLY; CREATE TABLE t1 (a varchar(1)); INSERT INTO t1 VALUES ('x'), ('y'); ANALYZE TABLE t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK FLUSH TABLES; set optimizer_use_condition_selectivity=3; SELECT * FROM t1 WHERE a <= 'w'; a set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4372: exists subquery in WHERE # with optimizer_use_condition_selectivity=3 # set use_stat_tables = PREFERABLY; CREATE TABLE t1 (a int); INSERT INTO t1 VALUES (1),(7),(4),(7),(0),(2),(9),(4),(0),(9),(1),(3),(8),(8); CREATE TABLE t2 (b int); INSERT INTO t2 VALUES (4),(5),(2),(5),(1),(1),(2); ANALYZE TABLE t1, t2; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK FLUSH TABLES; set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED SELECT * FROM t1, t2 WHERE EXISTS ( SELECT 1 FROM t1, t2 ) AND a != b OR a <= 4; id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t2 ALL NULL NULL NULL NULL 7 100.00 1 PRIMARY t1 ALL NULL NULL NULL NULL 14 100.00 Using where; Using join buffer (flat, BNL join) 2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 2 SUBQUERY t1 ALL NULL NULL NULL NULL 14 100.00 Using join buffer (flat, BNL join) Warnings: Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` join `test`.`t2` where ((1,exists(/* select#2 */ select 1 from `test`.`t1` join `test`.`t2` limit 1))) and `test`.`t1`.`a` <> `test`.`t2`.`b` or `test`.`t1`.`a` <= 4 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4363: selectivity of the condition a IS NULL OR IS NOT NULL # with optimizer_use_condition_selectivity=3 # set use_stat_tables = PREFERABLY; CREATE TABLE t1 (a int); INSERT INTO t1 VALUES (1),(7),(4),(7),(NULL),(2),(NULL),(4),(NULL),(NULL),(1),(3),(8),(8); ANALYZE TABLE t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK FLUSH TABLE t1; set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED SELECT * FROM t1 WHERE a IS NULL; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 14 28.57 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` is null EXPLAIN EXTENDED SELECT * FROM t1 WHERE a IS NOT NULL; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 14 71.43 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` is not null EXPLAIN EXTENDED SELECT * FROM t1 WHERE a IS NULL OR a IS NOT NULL; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 14 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` is null or `test`.`t1`.`a` is not null EXPLAIN EXTENDED SELECT * FROM t1 WHERE a IS NULL OR a < 5; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 14 69.39 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` is null or `test`.`t1`.`a` < 5 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4378: 2-way join with a materialized IN subquery in WHERE # when optimizer_use_condition_selectivity=4 # set use_stat_tables=PREFERABLY; set histogram_size=50; set histogram_type=SINGLE_PREC_HB; CREATE TABLE t1 (a INT) ENGINE=MyISAM; INSERT INTO t1 VALUES (8),(9),(6); CREATE TABLE t2 (b INT) ENGINE=MyISAM; INSERT INTO t2 VALUES (8),(1),(8),(9),(24),(6),(1),(6),(2),(4); CREATE TABLE t3 (ln VARCHAR(16)) ENGINE=MyISAM; INSERT INTO t3 VALUES ('smith'),('black'),('white'),('jones'), ('brown'),('taylor'),('anderson'),('taylor'); ANALYZE TABLE t1, t2, t3; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK test.t3 analyze status Engine-independent statistics collected test.t3 analyze status OK FLUSH TABLES; set optimizer_use_condition_selectivity=4; SELECT * FROM t1, t2 WHERE 'garcia' IN ( SELECT MIN( ln ) FROM t3 WHERE ln = 'sun' ); a b set histogram_size=@save_histogram_size; set histogram_type=@save_histogram_type; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2,t3; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4380: 2-way join with a materialized IN subquery in WHERE # when optimizer_use_condition_selectivity=3 # set use_stat_tables=PREFERABLY; CREATE TABLE t1 (a INT); INSERT INTO t1 VALUES (5),(9); CREATE TABLE t2 (b VARCHAR(8)); INSERT INTO t2 VALUES ('red'),('blue'); CREATE TABLE t3 (c VARCHAR(8), d VARCHAR(8)); INSERT INTO t3 VALUES ('white','black'),('cyan','yellow'); ANALYZE TABLE t1, t2, t3; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK test.t3 analyze status Engine-independent statistics collected test.t3 analyze status OK FLUSH TABLES; set optimizer_use_condition_selectivity=3; SELECT * FROM t1, t2 WHERE ( 'orange', 'green' ) IN ( SELECT MAX(c), MAX(d) FROM t3, t2 WHERE c >= d AND b = c ); a b set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2,t3; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4389: join with degenerated range condition in WHERE # when optimizer_use_condition_selectivity=3 # set use_stat_tables=PREFERABLY; CREATE TABLE t1 (f1 VARCHAR(1)); INSERT t1 VALUES ('p'),('q'); CREATE TABLE t2 (f2 VARCHAR(1)); INSERT INTO t2 VALUES ('o'),('v'),('f'),('f'),('e'),('l'),('j'),('p'),('r'),('j'), ('j'),('u'),('i'),('r'),('x'),('a'),('x'),('s'); ANALYZE TABLE t1, t2; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK FLUSH TABLES; SET optimizer_use_condition_selectivity=3; SELECT * FROM t1, t2 AS t2a, t2 AS t2b WHERE f1 <= 'a' AND t2a.f2 = f1; f1 f2 f2 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-4406: range condition for non-nullable column # when optimizer_use_condition_selectivity=3 # create table t1 (a int not null); insert into t1 values (7), (6), (4), (9), (1), (5), (2), (1), (3), (8); set use_stat_tables='preferably'; analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK flush table t1; set optimizer_use_condition_selectivity=3; select count(*) from t1 where a between 5 and 7; count(*) 3 explain extended select * from t1 where a between 5 and 7; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 10 25.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` between 5 and 7 alter table t1 change column a a int; analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK flush table t1; explain extended select * from t1 where a between 5 and 7; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 10 25.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` between 5 and 7 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; drop table t1; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-5200: impossible where with a semijoin subquery # when optimizer_use_condition_selectivity=2 # set use_stat_tables = 'preferably'; set optimizer_use_condition_selectivity = 2; CREATE TABLE t1 (i1 int) ENGINE=MyISAM; INSERT INTO t1 VALUES (0), (1); CREATE TABLE t2 (pk2 int, i2 int, c2 char(1), PRIMARY KEY(pk2)) ENGINE=MyISAM; INSERT INTO t2 VALUES (1,8,'m'), (2,9,'b'); CREATE TABLE t3 (c3 char(1), INDEX(c3)) ENGINE=MyISAM; INSERT INTO t3 VALUES ('v'), ('c'); ANALYZE TABLE t1,t2,t3; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK test.t3 analyze status Engine-independent statistics collected test.t3 analyze status OK SELECT * FROM t1 WHERE 2 IN ( SELECT pk2 FROM t2 LEFT JOIN t3 ON (c3 = c2 ) WHERE i2 = 3 ); i1 EXPLAIN EXTENDED SELECT * FROM t1 WHERE 2 IN ( SELECT pk2 FROM t2 LEFT JOIN t3 ON (c3 = c2 ) WHERE i2 = 3 ); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables Warnings: Note 1003 select `test`.`t1`.`i1` AS `i1` from `test`.`t1` semi join (`test`.`t2` left join `test`.`t3` on(`test`.`t3`.`c3` = 'b')) where 0 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2,t3; # # Bug mdev-5415: query over an information schema table # when optimizer_use_condition_selectivity=3 # set optimizer_use_condition_selectivity = 3; SELECT * FROM INFORMATION_SCHEMA.TRIGGERS WHERE SQL_MODE != ''; TRIGGER_CATALOG TRIGGER_SCHEMA TRIGGER_NAME EVENT_MANIPULATION EVENT_OBJECT_CATALOG EVENT_OBJECT_SCHEMA EVENT_OBJECT_TABLE ACTION_ORDER ACTION_CONDITION ACTION_STATEMENT ACTION_ORIENTATION ACTION_TIMING ACTION_REFERENCE_OLD_TABLE ACTION_REFERENCE_NEW_TABLE ACTION_REFERENCE_OLD_ROW ACTION_REFERENCE_NEW_ROW CREATED SQL_MODE DEFINER CHARACTER_SET_CLIENT COLLATION_CONNECTION DATABASE_COLLATION set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # Bug mdev-5630: always true conjunctive condition # when optimizer_use_condition_selectivity=3 # set use_stat_tables = 'preferably'; set optimizer_use_condition_selectivity = 3; CREATE TABLE t1 (a int) ENGINE=MyISAM; INSERT INTO t1 VALUES (10); CREATE TABLE t2 (id int, flag char(1), INDEX(id)) ENGINE=MyISAM; INSERT INTO t2 VALUES (100,'0'),(101,'1'); ANALYZE TABLE t1, t2; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK SELECT * FROM t1, t2 WHERE id = a AND ( a = 16 OR flag AND a != 6 ); a id flag DROP TABLE t1,t2; # # Bug mdev-4429: join with range condition whose selectivity == 0 # when optimizer_use_condition_selectivity=3 # CREATE TABLE language (lang_group INT, lang VARCHAR(16) PRIMARY KEY); INSERT INTO language VALUES (1,'Chinese'),(6,'English'),(1,'French'), (1,'German'),(1,'Italian'),(0,'Japanese'); CREATE TABLE country (code varchar(3) PRIMARY KEY, country_group INT DEFAULT NULL); INSERT INTO country VALUES ('USA',3),('FRA',5); CREATE TABLE continent (cont_group INT, cont varchar(16) PRIMARY KEY); INSERT INTO continent VALUES (1,'N.America'),(1,'S.America'),(3,'Australia'), (4,'Africa'),(5,'Antarctica'),(6,'Eurasia'); SET use_stat_tables=PREFERABLY; ANALYZE TABLE country, language, continent; Table Op Msg_type Msg_text test.country analyze status Engine-independent statistics collected test.country analyze status OK test.language analyze status Engine-independent statistics collected test.language analyze status OK test.continent analyze status Engine-independent statistics collected test.continent analyze status OK FLUSH TABLES; SET optimizer_use_condition_selectivity=3; SELECT * FROM language, country, continent WHERE country_group = lang_group AND lang_group IS NULL; lang_group lang code country_group cont_group cont EXPLAIN EXTENDED SELECT * FROM language, country, continent WHERE country_group = lang_group AND lang_group IS NULL; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE country ALL NULL NULL NULL NULL 2 50.00 Using where 1 SIMPLE language ALL NULL NULL NULL NULL 6 16.67 Using where; Using join buffer (flat, BNL join) 1 SIMPLE continent ALL NULL NULL NULL NULL 6 100.00 Using join buffer (incremental, BNL join) Warnings: Note 1003 select `test`.`language`.`lang_group` AS `lang_group`,`test`.`language`.`lang` AS `lang`,`test`.`country`.`code` AS `code`,`test`.`country`.`country_group` AS `country_group`,`test`.`continent`.`cont_group` AS `cont_group`,`test`.`continent`.`cont` AS `cont` from `test`.`language` join `test`.`country` join `test`.`continent` where `test`.`language`.`lang_group` = `test`.`country`.`country_group` and `test`.`country`.`country_group` is null set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; drop table language, country, continent; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-5191: performance degradation due to a suboptimal chosen plan # when optimizer_use_condition_selectivity=3 # set use_stat_tables = 'preferably'; set @@RAND_SEED1=810763568, @@RAND_SEED2=600681772; set TIMESTAMP=1394806993; create table t1 (a int, b int) engine=myisam; insert t1 values (rand()*1e5, rand()*1e5); insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; insert t1 select rand()*1e5, rand()*1e5 from t1; create table t2 (c int, d int, key(c), key(d)) engine=myisam; insert t2 select floor(rand()*1e5/2)*2, floor(rand()*1e5/3)*3 from t1; analyze table t1,t2; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status Table is already up to date set optimizer_use_condition_selectivity=1; explain extended select * from t1, t2, t1 as t3 where t1.b=t2.c and t2.d=t3.a and t3.b<5 and t1.a < 2000; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 262144 100.00 Using where 1 SIMPLE t2 ref c,d c 5 test.t1.b 5 100.00 1 SIMPLE t3 ALL NULL NULL NULL NULL 262144 100.00 Using where; Using join buffer (flat, BNL join) Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b` from `test`.`t1` join `test`.`t2` join `test`.`t1` `t3` where `test`.`t2`.`c` = `test`.`t1`.`b` and `test`.`t3`.`a` = `test`.`t2`.`d` and `test`.`t3`.`b` < 5 and `test`.`t1`.`a` < 2000 select * from t1, t2, t1 as t3 where t1.b=t2.c and t2.d=t3.a and t3.b<5 and t1.a < 2000; a b c d a b 1063 89366 89366 28296 28296 3 1495 89366 89366 28296 28296 3 221 56120 56120 28296 28296 3 961 24512 24512 85239 85239 4 set optimizer_use_condition_selectivity=3; explain extended select * from t1, t2, t1 as t3 where t1.b=t2.c and t2.d=t3.a and t3.b<5 and t1.a < 2000; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t3 ALL NULL NULL NULL NULL 262144 0.00 Using where 1 SIMPLE t2 ref c,d d 5 test.t3.a 7 100.00 1 SIMPLE t1 ALL NULL NULL NULL NULL 262144 2.00 Using where; Using join buffer (flat, BNL join) Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`c` AS `c`,`test`.`t2`.`d` AS `d`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b` from `test`.`t1` join `test`.`t2` join `test`.`t1` `t3` where `test`.`t1`.`b` = `test`.`t2`.`c` and `test`.`t2`.`d` = `test`.`t3`.`a` and `test`.`t3`.`b` < 5 and `test`.`t1`.`a` < 2000 select * from t1, t2, t1 as t3 where t1.b=t2.c and t2.d=t3.a and t3.b<5 and t1.a < 2000; a b c d a b 1063 89366 89366 28296 28296 3 1495 89366 89366 28296 28296 3 221 56120 56120 28296 28296 3 961 24512 24512 85239 85239 4 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; drop table t1,t2; set histogram_type=@save_histogram_type; set histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # Bug mdev-5931: no where condition after constant table row substitution # with optimizer_use_condition_selectivity=3 # CREATE TABLE t1 (a varchar(3), b varchar(3)) ENGINE=MyISAM; INSERT INTO t1 VALUES ('foo', 'foo'); CREATE TABLE t2 (c INT) ENGINE=MyISAM; INSERT INTO t2 VALUES (1), (2); set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED SELECT * FROM t1, t2 WHERE c >= 0 OR a = b ; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 100.00 1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Warnings: Note 1003 select 'foo' AS `a`,'foo' AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t2` where 1 SELECT * FROM t1, t2 WHERE c >= 0 OR a = b ; a b c foo foo 1 foo foo 2 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2; # # Bug mdev-6325: wrong selectivity of a column with ref access # 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; create table t2 (a int, b int, key(a)); insert into t2 select A.a + 10*B.a, 12345 from t0 A, t0 B, t0 C; set use_stat_tables='preferably'; set histogram_size=100; set optimizer_use_condition_selectivity=4; analyze table t1 persistent for all; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK analyze table t2 persistent for all; Table Op Msg_type Msg_text test.t2 analyze status Engine-independent statistics collected test.t2 analyze status Table is already up to date explain extended select * from t1 straight_join t2 where t1.a=t2.a and t1.a<10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 1.00 Using where 1 SIMPLE t2 ref a a 5 test.t1.a 10 100.00 Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` straight_join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`a` and `test`.`t1`.`a` < 10 explain extended select * from t1 straight_join t2 where t1.a=t2.a and t2.a<10; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 1.00 Using where 1 SIMPLE t2 ref a a 5 test.t1.a 10 100.00 Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` straight_join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`a` and `test`.`t1`.`a` < 10 set histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; drop table t0,t1,t2; # # Bug mdev-6843: col IS NULL in where condition when col is always NULL # 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; create table t2 (a int, b int); insert into t2 select NULL, a from t1; set use_stat_tables='preferably'; set histogram_size=100; set optimizer_use_condition_selectivity=4; analyze table t2 persistent for all; Table Op Msg_type Msg_text test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK explain extended select * from t2 a straight_join t2 b where a.a is null; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE a ALL NULL NULL NULL NULL 1000 100.00 Using where 1 SIMPLE b ALL NULL NULL NULL NULL 1000 100.00 Using join buffer (flat, BNL join) Warnings: Note 1003 select `test`.`a`.`a` AS `a`,`test`.`a`.`b` AS `b`,`test`.`b`.`a` AS `a`,`test`.`b`.`b` AS `b` from `test`.`t2` `a` straight_join `test`.`t2` `b` where `test`.`a`.`a` is null set histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; drop table t0,t1,t2; # # Bug mdev-7316: a conjunct in WHERE with selectivity == 0 # CREATE TABLE t1 (a varchar(16), b int, PRIMARY KEY(a), KEY(b)); INSERT INTO t1 VALUES ('USAChinese',10), ('USAEnglish',20), ('USAFrench',30); CREATE TABLE t2 (i int); INSERT INTO t2 VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(1),(2),(3),(4); ANALYZE TABLE t1, t2; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK test.t2 analyze status Engine-independent statistics collected test.t2 analyze status OK set use_stat_tables='preferably'; set optimizer_use_condition_selectivity=3; EXPLAIN EXTENDED SELECT * FROM t1, t2 WHERE a <> 'USARussian' AND b IS NULL; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ref PRIMARY,b b 5 const 1 100.00 Using index condition; Using where 1 SIMPLE t2 ALL NULL NULL NULL NULL 14 100.00 Using join buffer (flat, BNL join) Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`i` AS `i` from `test`.`t1` join `test`.`t2` where `test`.`t1`.`a` <> 'USARussian' and `test`.`t1`.`b` is null SELECT * FROM t1, t2 WHERE a <> 'USARussian' AND b IS NULL; a b i set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1,t2; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-11096: range condition over column without statistical data # set use_stat_tables='preferably'; set optimizer_use_condition_selectivity=3; create table t1(col1 char(32)); insert into t1 values ('a'),('b'),('c'),('d'), ('e'),('f'),('g'),('h'); analyze table t1 persistent for columns () indexes (); Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK explain extended select * from t1 where col1 > 'b' and col1 < 'e'; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 8 100.00 Using where Warnings: Note 1003 select `test`.`t1`.`col1` AS `col1` from `test`.`t1` where `test`.`t1`.`col1` > 'b' and `test`.`t1`.`col1` < 'e' select * from t1 where col1 > 'b' and col1 < 'e'; col1 c d drop table t1; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-9628: unindexed blob column without min-max statistics # with optimizer_use_condition_selectivity=3 # set use_stat_tables='preferably'; set optimizer_use_condition_selectivity=3; create table t1(col1 char(32)); insert into t1 values ('a'),('b'),('c'),('d'), ('e'),('f'),('g'),('h'); analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK create table t2(col1 text); insert into t2 values ('a'),('b'),('c'),('d'), ('e'),('f'),('g'),('h'); analyze table t2; Table Op Msg_type Msg_text test.t2 analyze status Engine-independent statistics collected test.t2 analyze Warning Engine-independent statistics are not collected for column 'col1' test.t2 analyze status OK select * from t1 where col1 > 'b' and col1 < 'd'; col1 c explain extended select * from t1 where col1 > 'b' and col1 < 'd'; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 8 28.57 Using where Warnings: Note 1003 select `test`.`t1`.`col1` AS `col1` from `test`.`t1` where `test`.`t1`.`col1` > 'b' and `test`.`t1`.`col1` < 'd' select * from t2 where col1 > 'b' and col1 < 'd'; col1 c explain extended select * from t2 where col1 > 'b' and col1 < 'd'; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 ALL NULL NULL NULL NULL 8 100.00 Using where Warnings: Note 1003 select `test`.`t2`.`col1` AS `col1` from `test`.`t2` where `test`.`t2`.`col1` > 'b' and `test`.`t2`.`col1` < 'd' select * from t2 where col1 < 'b' and col1 > 'd'; col1 explain extended select * from t2 where col1 < 'b' and col1 > 'd'; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 ALL NULL NULL NULL NULL 8 100.00 Using where Warnings: Note 1003 select `test`.`t2`.`col1` AS `col1` from `test`.`t2` where `test`.`t2`.`col1` < 'b' and `test`.`t2`.`col1` > 'd' drop table t1,t2; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; set use_stat_tables=@save_use_stat_tables; # # Bug mdev-11364: IS NULL over not nullable datetime column # in mergeable derived # set use_stat_tables='preferably'; set optimizer_use_condition_selectivity=4; set HISTOGRAM_SIZE = 255; CREATE TABLE t1 (t TIME, d DATE NOT NULL); INSERT INTO t1 VALUES ('10:00:00', '0000-00-00'),('11:00:00','0000-00-00'); ANALYZE TABLE t1; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK SELECT * FROM (SELECT t FROM t1 WHERE d IS NULL) sq; t 10:00:00 11:00:00 DROP TABLE t1; # # MDEV-16374: filtered shows 0 for materilization scan for a semi join, which makes optimizer # always pick materialization scan over materialization lookup # create table t0(a int); insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t1 (a int, b int); insert into t1 values (0,0),(1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9),(10,10), (11,11),(12,12),(13,13),(14,14),(15,15); set @@optimizer_use_condition_selectivity=2; explain extended select * from t1 where a in (select max(a) from t1 group by b); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 16 100.00 Using where 1 PRIMARY eq_ref distinct_key distinct_key 4 test.t1.a 1 100.00 2 MATERIALIZED t1 ALL NULL NULL NULL NULL 16 100.00 Using temporary Warnings: Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from (/* select#2 */ select max(`test`.`t1`.`a`) from `test`.`t1` group by `test`.`t1`.`b`) join `test`.`t1` where ``.`max(a)` = `test`.`t1`.`a` select * from t1 where a in (select max(a) from t1 group by b); a b 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 11 11 12 12 13 13 14 14 15 15 set @@optimizer_use_condition_selectivity=1; explain extended select * from t1 where a in (select max(a) from t1 group by b); id select_type table type possible_keys key key_len ref rows filtered Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 16 100.00 Using where 1 PRIMARY eq_ref distinct_key distinct_key 4 test.t1.a 1 100.00 2 MATERIALIZED t1 ALL NULL NULL NULL NULL 16 100.00 Using temporary Warnings: Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from (/* select#2 */ select max(`test`.`t1`.`a`) from `test`.`t1` group by `test`.`t1`.`b`) join `test`.`t1` where ``.`max(a)` = `test`.`t1`.`a` select * from t1 where a in (select max(a) from t1 group by b); a b 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 11 11 12 12 13 13 14 14 15 15 drop table t1,t0; set histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; set use_stat_tables=@save_use_stat_tables; # # MDEV-15306: Wrong/Unexpected result with the value # optimizer_use_condition_selectivity set to 4 # CREATE TABLE t1 (a INT); INSERT INTO t1 VALUES (1), (2), (3), (4), (5), (6), (7), (8), (9), (10); CREATE FUNCTION f1() RETURNS INT DETERMINISTIC BEGIN SET @cnt := @cnt + 1; RETURN 1; END;| set @save_optimizer_use_condition_selectivity=@@optimizer_use_condition_selectivity; set @save_use_stat_tables= @@use_stat_tables; set @@use_stat_tables='complementary'; set @@optimizer_use_condition_selectivity=4; SET @cnt= 0; SELECT * FROM t1 WHERE a = f1(); a 1 SELECT @cnt; @cnt 1 set @@use_stat_tables='preferably'; analyze table t1 persistent for all; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK SET @cnt := 0; set @@optimizer_use_condition_selectivity=4; SELECT * FROM t1 WHERE a = f1(); a 1 SELECT @cnt; @cnt 2 alter table t1 force; drop table t1; drop function f1; # # MDEV-19834 Selectivity of an equality condition discounted twice # create table t1 (a int, b int, key (b), key (a)); insert into t1 select (rand(1)*1000)/10, (rand(1001)*1000)/50 from seq_1_to_1000; analyze table t1 ; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status Table is already up to date # Check what info the optimizer has about selectivities explain extended select * from t1 use index () where a in (17,51,5); id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 2.90 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`a` in (17,51,5) explain extended select * from t1 use index () where b=2; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 5.90 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`b` = 2 # Now, the equality is used for ref access, while the range condition # gives selectivity data explain extended select * from t1 where a in (17,51,5) and b=2; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ref|filter b,a b|a 5|5 const 58 (3%) 2.90 Using where; Using rowid filter Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`b` = 2 and `test`.`t1`.`a` in (17,51,5) drop table t1; set use_stat_tables= @save_use_stat_tables; set @@histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; # # MDEV-20576: failing assertion DBUG_ASSERT(0.0 < sel && sel <= 1) # set @@optimizer_use_condition_selectivity=2; set names utf8; CREATE DATABASE world; use world; CREATE TABLE Country ( Code char(3) NOT NULL default '', Name char(52) NOT NULL default '', SurfaceArea float(10,2) NOT NULL default '0.00', Population int(11) NOT NULL default '0', Capital int(11) default NULL, PRIMARY KEY (Code), UNIQUE INDEX (Name) ); CREATE TABLE City ( ID int(11) NOT NULL auto_increment, Name char(35) NOT NULL default '', Country char(3) NOT NULL default '', Population int(11) NOT NULL default '0', PRIMARY KEY (ID), INDEX (Population), INDEX (Country) ); CREATE TABLE CountryLanguage ( Country char(3) NOT NULL default '', Language char(30) NOT NULL default '', Percentage float(3,1) NOT NULL default '0.0', PRIMARY KEY (Country, Language), INDEX (Percentage) ); CREATE INDEX Name ON City(Name); CREATE INDEX CountryPopulation ON City(Country,Population); CREATE INDEX CountryName ON City(Country,Name); set @@optimizer_use_condition_selectivity=2; EXPLAIN SELECT * FROM City WHERE Country='FIN'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE City ref Country,CountryPopulation,CountryName CountryName 3 const 5 Using index condition DROP DATABASE world; use test; CREATE TABLE t1 ( a INT, b INT NOT NULL, c char(100), KEY (b, c), KEY (b, a, c) ) ENGINE=MyISAM DEFAULT CHARSET = utf8; INSERT INTO t1 VALUES (1, 1, 1), (2, 2, 2), (3, 3, 3), (4, 4, 4), (5, 5, 5), (6, 6, 6), (7, 7, 7), (8, 8, 8), (9, 9, 9); INSERT INTO t1 SELECT a + 10, b, c FROM t1; INSERT INTO t1 SELECT a + 20, b, c FROM t1; INSERT INTO t1 SELECT a + 40, b, c FROM t1; INSERT INTO t1 SELECT a + 80, b, c FROM t1; INSERT INTO t1 SELECT a + 160, b, c FROM t1; INSERT INTO t1 SELECT a + 320, b, c FROM t1; INSERT INTO t1 SELECT a + 640, b, c FROM t1; INSERT INTO t1 SELECT a + 1280, b, c FROM t1 LIMIT 80; EXPLAIN SELECT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 9; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range b,b_2 b 4 NULL 226 Using where SELECT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 9; a 2071 2061 2051 2041 2031 2021 2011 2001 1991 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; DROP TABLE t1; # # MDEV-20424: New default value for optimizer_use_condition-selectivity # leads to bad plan # create table t1(a int, b int, c int, d int, key(a,b)); insert into t1 select 50,seq-1,seq-1,seq from seq_1_to_10; insert into t1 select seq-1,seq-1,seq-1,seq from seq_1_to_100 limit 90; create table t2(a int, b int, c int, primary key(a)); insert into t2 select seq-1,seq-1,seq-1 from seq_1_to_100; create table t3(a int, b int, c int, primary key(a)); insert into t3 select seq-1,seq-1,seq-1 from seq_1_to_100 limit 30; set optimizer_use_condition_selectivity=1; explain extended select t1.b,t2.a,t3.a,t3.b from t1,t2,t3 where t1.c = t2.a AND t1.d = t3.a and t1.a = 50 and t1.b <= 100; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 range a a 10 NULL 9 100.00 Using index condition; Using where 1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.d 1 100.00 1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.c 1 100.00 Using index Warnings: Note 1003 select `test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b` from `test`.`t1` join `test`.`t2` join `test`.`t3` where `test`.`t2`.`a` = `test`.`t1`.`c` and `test`.`t3`.`a` = `test`.`t1`.`d` and `test`.`t1`.`a` = 50 and `test`.`t1`.`b` <= 100 select t1.b,t2.a,t3.a,t3.b from t1,t2,t3 where t1.c = t2.a AND t1.d = t3.a and t1.a = 50 and t1.b <= 100; b a a b 0 0 1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4 5 5 5 5 6 6 6 6 7 7 7 7 8 8 8 8 9 9 9 9 10 10 set optimizer_use_condition_selectivity=2; explain extended select t1.b,t2.a,t3.a,t3.b from t1,t2,t3 where t1.c = t2.a AND t1.d = t3.a and t1.a = 50 and t1.b <= 100; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 range a a 10 NULL 9 9.00 Using index condition; Using where 1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.d 1 100.00 1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.c 1 100.00 Using index Warnings: Note 1003 select `test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b` from `test`.`t1` join `test`.`t2` join `test`.`t3` where `test`.`t2`.`a` = `test`.`t1`.`c` and `test`.`t3`.`a` = `test`.`t1`.`d` and `test`.`t1`.`a` = 50 and `test`.`t1`.`b` <= 100 select t1.b,t2.a,t3.a,t3.b from t1,t2,t3 where t1.c = t2.a AND t1.d = t3.a and t1.a = 50 and t1.b <= 100; b a a b 0 0 1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4 5 5 5 5 6 6 6 6 7 7 7 7 8 8 8 8 9 9 9 9 10 10 set optimizer_use_condition_selectivity= @@optimizer_use_condition_selectivity; drop table t1,t2,t3; # # MDEV-20519: Query plan regression with optimizer_use_condition_selectivity=4 # create table t1 (id int, a int, PRIMARY KEY(id), key(a)); insert into t1 select seq,seq from seq_1_to_100; create table t2 (id int, a int, b int, PRIMARY KEY(id), key(a), key(b)); insert into t2 select seq,seq,seq from seq_1_to_100; set optimizer_switch='exists_to_in=off'; set optimizer_use_condition_selectivity=2; SELECT * FROM t1 WHERE EXISTS (SELECT * FROM t1 A INNER JOIN t2 ON t2.a = A.id WHERE A.a=t1.a AND t2.b < 20); id a 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 11 11 12 12 13 13 14 14 15 15 16 16 17 17 18 18 19 19 explain SELECT * FROM t1 WHERE EXISTS (SELECT * FROM t1 A INNER JOIN t2 ON t2.a = A.id WHERE A.a=t1.a AND t2.b < 20); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 100 Using where 2 DEPENDENT SUBQUERY A ref PRIMARY,a a 5 test.t1.a 1 2 DEPENDENT SUBQUERY t2 ref|filter a,b a|b 5|5 test.A.id 1 (10%) Using where; Using rowid filter EXPLAIN SELECT * FROM t1 A, t1 B WHERE A.a = B.a and A.id = 65; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE A const PRIMARY,a PRIMARY 4 const 1 1 SIMPLE B ref a a 5 const 1 explain SELECT * FROM t1 WHERE EXISTS (SELECT * FROM t1 A INNER JOIN t2 ON t2.a = A.id WHERE A.a=t1.a AND t2.b < 20); id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 ALL NULL NULL NULL NULL 100 Using where 2 DEPENDENT SUBQUERY A ref PRIMARY,a a 5 test.t1.a 1 2 DEPENDENT SUBQUERY t2 ref|filter a,b a|b 5|5 test.A.id 1 (10%) Using where; Using rowid filter set optimizer_switch= @save_optimizer_switch; set optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity; drop table t1,t2; # # MDEV-21495: Conditional jump or move depends on uninitialised value in sel_arg_range_seq_next # CREATE TABLE t1(a INT, b INT); INSERT INTO t1 SELECT seq, seq from seq_1_to_100; set optimizer_use_condition_selectivity=4; ANALYZE TABLE t1 PERSISTENT FOR ALL; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK SELECT * from t1 WHERE a = 5 and b = 5; a b 5 5 set optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity; drop table t1; # End of 10.1 tests # # MDEV-22583: Selectivity for BIT columns in filtered column for EXPLAIN is incorrect # SET optimizer_use_condition_selectivity=4; SET histogram_size=255; CREATE TABLE t1 (a BIT(32), b INT); INSERT INTO t1 VALUES (80, 80), (81, 81), (82, 82); ANALYZE TABLE t1 PERSISTENT FOR ALL; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK EXPLAIN EXTENDED SELECT * from t1 where t1.a >= 81; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 3 66.67 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` >= 81 SELECT HEX(a), b from t1 where t1.a >= 81; HEX(a) b 51 81 52 82 set optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity; set histogram_size=@save_histogram_size; DROP TABLE t1; # # MDEV-19474: Histogram statistics are used even with optimizer_use_condition_selectivity=3 # CREATE TABLE t1(a int); INSERT INTO t1 values (1),(2),(2),(3),(4); SET optimizer_use_condition_selectivity=4; SET histogram_size= 255; set use_stat_tables='preferably'; ANALYZE TABLE t1 PERSISTENT FOR ALL; Table Op Msg_type Msg_text test.t1 analyze status Engine-independent statistics collected test.t1 analyze status OK EXPLAIN EXTENDED SELECT * FROM t1 WHERE a=2; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 5 40.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` = 2 SET optimizer_use_condition_selectivity=3; # filtered should show 25 % EXPLAIN EXTENDED SELECT * FROM t1 WHERE a=2; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 5 25.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` = 2 FLUSH TABLES; EXPLAIN EXTENDED SELECT * FROM t1 WHERE a=2; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 5 25.00 Using where Warnings: Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` = 2 set optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity; set histogram_size=@save_histogram_size; set use_stat_tables= @save_use_stat_tables; DROP TABLE t1; # End of 10.2 tests set @@global.histogram_size=@save_histogram_size;