15 lines
541 B
Plaintext
15 lines
541 B
Plaintext
drop table if exists t1;
|
|
create table t1(n int not null, key(n)) delay_key_write = 1;
|
|
analyze table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 analyze status OK
|
|
select count(distinct n) from t1;
|
|
count(distinct n)
|
|
100
|
|
explain select count(distinct n) from t1;
|
|
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
|
|
1 SIMPLE t1 NULL range n n 4 NULL 101 100.00 Using index for group-by
|
|
Warnings:
|
|
Note 1003 /* select#1 */ select count(distinct `test`.`t1`.`n`) AS `count(distinct n)` from `test`.`t1`
|
|
drop table t1;
|