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SET DEFAULT_STORAGE_ENGINE='tokudb';
DROP TABLE IF EXISTS t1;
create table t1(a int, b int, c int, d int, primary key(a), clustering key(b), key (c))engine=tokudb;
insert into t1 values (1,10,100,1000),(2,20,200,2000),(3,30,300,3000),(4,40,400,4000),(5,50,500,5000),(6,60,600,6000),(7,70,700,7000),(8,80,800,8000),(9,90,900,9000);
explain select * from t1 where a > 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL NULL; Using where
select * from t1 where a > 5;
a b c d
6 60 600 6000
7 70 700 7000
8 80 800 8000
9 90 900 9000
explain select * from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where
select * from t1 where b > 30;
a b c d
4 40 400 4000
5 50 500 5000
6 60 600 6000
7 70 700 7000
8 80 800 8000
9 90 900 9000
explain select * from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select * from t1 where c > 750;
a b c d
8 80 800 8000
9 90 900 9000
explain select a from t1 where a > 8;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL NULL; Using where; Using index
select a from t1 where a > 8;
a
9
explain select a,b from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where; Using index
select a,b from t1 where b > 30;
a b
4 40
5 50
6 60
7 70
8 80
9 90
explain select a,b from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select a,c from t1 where c > 750;
a c
8 800
9 900
alter table t1 add clustering index bdca(b,d,c,a);
insert into t1 values (10,10,10,10);
alter table t1 drop index bdca;
alter table t1 drop primary key;
explain select * from t1 where a > 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL NULL; Using where
select * from t1 where a > 5;
a b c d
6 60 600 6000
7 70 700 7000
8 80 800 8000
9 90 900 9000
10 10 10 10
explain select * from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where
select * from t1 where b > 30;
a b c d
4 40 400 4000
5 50 500 5000
6 60 600 6000
7 70 700 7000
8 80 800 8000
9 90 900 9000
explain select * from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select * from t1 where c > 750;
a b c d
8 80 800 8000
9 90 900 9000
explain select b from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where; Using index
select b from t1 where b > 30;
b
40
50
60
70
80
90
explain select b from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select c from t1 where c > 750;
c
800
900
alter table t1 add e varchar(20);
alter table t1 add primary key (a);
explain select * from t1 where a > 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL NULL; Using where
select * from t1 where a > 5;
a b c d e
6 60 600 6000 NULL
7 70 700 7000 NULL
8 80 800 8000 NULL
9 90 900 9000 NULL
10 10 10 10 NULL
explain select * from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where
select * from t1 where b > 30;
a b c d e
4 40 400 4000 NULL
5 50 500 5000 NULL
6 60 600 6000 NULL
7 70 700 7000 NULL
8 80 800 8000 NULL
9 90 900 9000 NULL
explain select * from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select * from t1 where c > 750;
a b c d e
8 80 800 8000 NULL
9 90 900 9000 NULL
explain select a from t1 where a > 8;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL NULL; Using where; Using index
select a from t1 where a > 8;
a
9
10
explain select a,b from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where; Using index
select a,b from t1 where b > 30;
a b
4 40
5 50
6 60
7 70
8 80
9 90
explain select a,b from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select a,c from t1 where c > 750;
a c
8 800
9 900
alter table t1 drop primary key;
explain select * from t1 where a > 5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL NULL; Using where
select * from t1 where a > 5;
a b c d e
6 60 600 6000 NULL
7 70 700 7000 NULL
8 80 800 8000 NULL
9 90 900 9000 NULL
10 10 10 10 NULL
explain select * from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where
select * from t1 where b > 30;
a b c d e
4 40 400 4000 NULL
5 50 500 5000 NULL
6 60 600 6000 NULL
7 70 700 7000 NULL
8 80 800 8000 NULL
9 90 900 9000 NULL
explain select * from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select * from t1 where c > 750;
a b c d e
8 80 800 8000 NULL
9 90 900 9000 NULL
explain select b from t1 where b > 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range b b 5 NULL NULL; Using where; Using index
select b from t1 where b > 30;
b
40
50
60
70
80
90
explain select b from t1 where c > 750;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range c c 5 NULL NULL; Using where
select c from t1 where c > 750;
c
800
900
drop table t1;
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