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create table t1 (c1 int not null, c2 int, unique index(c1), index (c2)) engine=innodb;
insert into t1 (c1, c2) select 1, round(rand()*100);
insert into t1 (c1, c2) select (select max(c1) from t1) + c1, c1*93563%100 from t1;
insert into t1 (c1, c2) select (select max(c1) from t1) + c1, c1*93563%100 from t1;
insert into t1 (c1, c2) select (select max(c1) from t1) + c1, c1*93563%100 from t1;
select count(*) from t1;
count(*)
8
explain select * from t1 where c2 = 1 order by c1;
id 1
select_type SIMPLE
table t1
type ref
possible_keys c2
key c2
key_len 5
ref const
rows 1
Extra Using where; Using index
drop table t1;
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