drop table if exists tjuo1,tjuo2,tjuo3;
create table tjuo1 (pk int,c1 int, primary key(pk));
create table tjuo2 (pk int,c1 int, c2 int, primary key(pk));
create table tjuo3 (pk int,c2 int, primary key(pk));
insert into tjuo1 values(1, 11), (2, 12), (3, 13);
insert into tjuo2 values(4, 11, 21), (5, 12, 22), (6, 13, 23);
insert into tjuo3 values(7, 21), (8, 22), (9, 23);
select * from tjuo1;
pk	c1
1	11
2	12
3	13
select * from tjuo2;
pk	c1	c2
4	11	21
5	12	22
6	13	23
select * from tjuo3;
pk	c2
7	21
8	22
9	23
SELECT * FROM tjuo1 JOIN  (SELECT * FROM tjuo2) as tjuo2_alias  on tjuo1.c1= tjuo2_alias.c1;
pk	c1	pk	c1	c2
1	11	4	11	21
2	12	5	12	22
3	13	6	13	23
SELECT * FROM tjuo1 RIGHT JOIN (SELECT * FROM tjuo2) as tjuo2_alias  USING (c1);
c1	pk	c2	pk
11	4	21	1
12	5	22	2
13	6	23	3
SELECT * FROM tjuo1 JOIN tjuo2 on tjuo1.c1=tjuo2.c1 JOIN tjuo3 on tjuo2.c2=tjuo3.c2;
pk	c1	pk	c1	c2	pk	c2
1	11	4	11	21	7	21
2	12	5	12	22	8	22
3	13	6	13	23	9	23
SELECT * FROM tjuo1 RIGHT JOIN tjuo2 USING (c1) RIGHT JOIN tjuo3 USING (c2);
c2	pk	c1	pk	pk
21	7	11	4	1
22	8	12	5	2
23	9	13	6	3
SELECT * FROM tjuo1 RIGHT JOIN (SELECT * FROM tjuo2) as tjuo2_alias USING (c1) RIGHT JOIN tjuo3 USING (c2);
c2	pk	c1	pk	pk
21	7	11	4	1
22	8	12	5	2
23	9	13	6	3
SELECT * FROM  (SELECT * FROM tjuo1) tjuo1_alias RIGHT JOIN (SELECT * FROM tjuo2) as tjuo2_alias USING (c1) RIGHT JOIN (SELECT * FROM tjuo3) as tjuo3_alias USING (c2);
c2	pk	c1	pk	pk
21	7	11	4	1
22	8	12	5	2
23	9	13	6	3
SELECT * FROM  (SELECT * FROM tjuo1) tjuo1_alias RIGHT JOIN tjuo2  USING (c1) RIGHT JOIN (SELECT * FROM tjuo3) as tjuo3_alias USING (c2);
c2	pk	c1	pk	pk
21	7	11	4	1
22	8	12	5	2
23	9	13	6	3
SELECT * FROM  (SELECT c2 FROM tjuo1 as i1 JOIN (SELECT * FROM tjuo2) as i2 USING (c1) ) as t12 RIGHT JOIN (SELECT * FROM tjuo3) as tjuo3_alias USING (c2);
c2	pk
21	7
22	8
23	9
SELECT * FROM  (SELECT c2 FROM tjuo1 as i1 JOIN (SELECT * FROM tjuo2) as i2 USING (c1) ) as t12;
c2
21
22
23
drop table tjuo1, tjuo2, tjuo3;