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create table t1(a bit(1), b int auto_increment ,id int, index(a,b));
insert into t1 values(1,null,1);
insert into t1 values(1,null,2);
insert into t1 values(0,null,3);
insert into t1 values(0,null,4);
select a+0, b as auto_increment , id from t1 order by id;
a+0 auto_increment id
1 1 1
1 2 2
0 1 3
0 2 4
drop table t1;
create table t1(a int auto_increment, b bit(5) ,id int, index (b,a));
insert into t1 values(null,b'1',1);
insert into t1 values(null,b'1',2);
insert into t1 values(null,b'11',3);
insert into t1 values(null,b'11',4);
select a as auto_increment, b+0, id from t1 order by id;
auto_increment b+0 id
1 1 1
2 1 2
1 3 3
2 3 4
drop table t1;
create table t1(a bit(1), b int auto_increment , c bit(1) , d bit(1), id int,index(a,c,b,d));
insert into t1 values(1,null,1,1,1);
insert into t1 values(1,null,1,1,2);
insert into t1 values(0,null,1,1,3);
insert into t1 values(1,null,0,1,4);
select a+0, b as auto_increment, c+0, d+0, id from t1 order by id;
a+0 auto_increment c+0 d+0 id
1 1 1 1 1
1 2 1 1 2
0 1 1 1 3
1 1 0 1 4
drop table t1;
CREATE TABLE t1 (b BIT(1), pk INTEGER AUTO_INCREMENT PRIMARY KEY);
ALTER TABLE t1 ADD INDEX(b,pk);
INSERT INTO t1 VALUES (1,b'1');
ALTER TABLE t1 DROP PRIMARY KEY;
select b+0, pk as auto_increment from t1;
b+0 auto_increment
1 1
DROP TABLE t1;
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