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SET DEFAULT_STORAGE_ENGINE = 'tokudb';
DROP TABLE IF EXISTS foo;
create table foo (a int, b int, c int, primary key (a,b));
insert into foo values (1,10,100),(2,20,200),(3,30,300),(4,40,400),(5,50,500),(6,60,600);
insert into foo values (1,100,100),(2,200,200),(3,300,300),(4,400,400),(5,500,500),(6,600,600);
select * from foo;
a b c
1 10 100
1 100 100
2 20 200
2 200 200
3 30 300
3 300 300
4 40 400
4 400 400
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a=4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref PRIMARY PRIMARY 4 const NULL;
select * from foo where a=4;
a b c
4 40 400
4 400 400
explain select * from foo where a>4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range PRIMARY PRIMARY 4 NULL NULL; Using where
select * from foo where a>4;
a b c
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a<3 order by a desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range PRIMARY PRIMARY 4 NULL NULL; Using where
select * from foo where a<3 order by a desc;
a b c
2 200 200
2 20 200
1 100 100
1 10 100
explain select * from foo where a>=4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range PRIMARY PRIMARY 4 NULL NULL; Using where
select * from foo where a>=4;
a b c
4 40 400
4 400 400
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a<=2 order by a desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range PRIMARY PRIMARY 4 NULL NULL; Using where
select * from foo where a<=2 order by a desc;
a b c
2 200 200
2 20 200
1 100 100
1 10 100
explain select * from foo where a=4 order by b desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref PRIMARY PRIMARY 4 const NULL; Using where
select * from foo where a=4 order by b desc;
a b c
4 400 400
4 40 400
alter table foo drop primary key;
alter table foo add index clst_a(a,b) clustering=yes;
explain select * from foo where a=4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref clst_a clst_a 4 const NULL; Using index
select * from foo where a=4;
a b c
4 40 400
4 400 400
explain select * from foo where a>4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range clst_a clst_a 4 NULL NULL; Using where; Using index
select * from foo where a>4;
a b c
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a<3 order by a desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range clst_a clst_a 4 NULL NULL; Using where; Using index
select * from foo where a<3 order by a desc;
a b c
2 200 200
2 20 200
1 100 100
1 10 100
explain select * from foo where a>=4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range clst_a clst_a 4 NULL NULL; Using where; Using index
select * from foo where a>=4;
a b c
4 40 400
4 400 400
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a<=2 order by a desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range clst_a clst_a 4 NULL NULL; Using where; Using index
select * from foo where a<=2 order by a desc;
a b c
2 200 200
2 20 200
1 100 100
1 10 100
explain select * from foo where a=4 order by b desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref clst_a clst_a 4 const NULL; Using where; Using index
select * from foo where a=4 order by b desc;
a b c
4 400 400
4 40 400
alter table foo drop index clst_a;
alter table foo add index (a,b);
explain select * from foo where a=4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref a a 4 const NULL;
select * from foo where a=4;
a b c
4 40 400
4 400 400
explain select * from foo where a>4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range a a 4 NULL NULL; Using where
select * from foo where a>4;
a b c
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a<3 order by a desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range a a 4 NULL NULL; Using where
select * from foo where a<3 order by a desc;
a b c
2 200 200
2 20 200
1 100 100
1 10 100
explain select * from foo where a>=4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range a a 4 NULL NULL; Using where
select * from foo where a>=4;
a b c
4 40 400
4 400 400
5 50 500
5 500 500
6 60 600
6 600 600
explain select * from foo where a<=2 order by a desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo range a a 4 NULL NULL; Using where
select * from foo where a<=2 order by a desc;
a b c
2 200 200
2 20 200
1 100 100
1 10 100
explain select * from foo where a=4 order by b desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref a a 4 const NULL; Using where
select * from foo where a=4 order by b desc;
a b c
4 400 400
4 40 400
DROP TABLE foo;
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