1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
create table t1 (a int primary key);
insert into t1 values (1),(2),(3),(4),(100),(200);
explain select * from t1 order by a;
select * from t1 order by a;
explain select * from t1 where a>4;
select * from t1 where a>4;
explain select * from t1 where a<4;
select * from t1 where a<4;
explain select * from t1 where a=4;
select * from t1 where a=4;
drop table t1;
create table t1 (a int primary key, b varchar(100));
insert into t1 values (1, "hello"), (2, "world"), (3, "Beaker"), (4, "Cricket");
EXPLAIN SELECT b FROM t1 WHERE a=1;
SELECT b FROM t1 WHERE a=1;
EXPLAIN SELECT b FROM t1 WHERE a=2;
SELECT b FROM t1 WHERE a=2;
EXPLAIN SELECT b FROM t1 WHERE a=3;
SELECT b FROM t1 WHERE a=3;
EXPLAIN SELECT b FROM t1 WHERE a=4;
SELECT b FROM t1 WHERE a=4;
DROP TABLE t1;
|