SQL tricky query - sql

Question

I have this query
select lab.IDLAB,
lab.NOMLAB,
lab.CAPACIDAD
from laboratorio lab
inner join DETALLESOLICITUD det on det.IDLAB = lab.IDLAB
inner join dia on dia.iddia = det.iddia
inner join bloque blo on blo.idbloque = det.idbloque
inner join solicitud sol on sol.IDSOLICITUD=det.IDSOLICITUD
where blo.idbloque = 1
and dia.iddia = 1
and sol.estado in (1,2)
which returns:
IDLAB | NOMLAB | CAPACIDAD
----------------------------
1 | LCOMP1 | 22
And it does exactly what I want it to do. Now I want to get all the records from the table laboratorios that doesn't appear in this query. For example my laboratorios table has contents:
IDLAB | NOMLAB | CAPACIDAD
----------------------------
1 | LCOMP1 | 22
2 | LCOMP2 | 31
3 | LCOMP3 | 17
4 | LCOMP4 | 26
And I want the following output:
IDLAB | NOMLAB | CAPACIDAD
----------------------------
2 | LCOMP2 | 31
3 | LCOMP3 | 17
4 | LCOMP4 | 26
I tried with a not exists statement this way:
select *
from laboratorio
where not exists(
select lab.idlab, lab.nomlab, lab.CAPACIDAD
from laboratorio lab
inner join DETALLESOLICITUD det on det.idlab = lab.idlab
inner join dia on dia.iddia = det.iddia
inner join bloque blo on blo.idbloque = det.idbloque
inner join solicitud sol on sol.IDSOLICITUD = det.IDSOLICITUD
where blo.idbloque = 1
and dia.iddia = 1
and sol.estado in(1,2)
);
and this way:
select *
from laboratorio
where not exists(
select det.IDLAB
from DETALLESOLICITUD det
inner join dia on dia.iddia = det.iddia
inner join bloque blo on blo.idbloque = det.idbloque
inner join solicitud sol on sol.IDSOLICITUD = det.IDSOLICITUD
where blo.idbloque = 1
and dia.iddia = 1
and sol.estado in(1,2)
);
but both returns nothing. Any help will be really appreciate.

Answer 1

Your sub-queries return rows. You know that because of the first query. But where not exists is only true when the sub-query returns no rows. Check it out:
SQL> select * from dual
2 /
D
-
X
SQL> select * from dual
2 where not exists (select * from dual
3 where dummy = 'X')
4 /
no rows selected
SQL> select * from dual
2 where not exists (select * from dual
3 where dummy = 'Y')
4 /
D
-
X
SQL>
So what you need to do is correlate the outer query with the sub-query. Easiest way to do this:
select * from laboratorio
where (idlab, nomlab, CAPACIDAD)
not in (select lab.idlab, lab.nomlab, lab.CAPACIDAD
from laboratorio lab
inner join DETALLESOLICITUD det on det.idlab = lab.idlab
inner join dia on dia.iddia = det.iddia
inner join bloque blo on blo.idbloque = det.idbloque
inner join solicitud sol on sol.IDSOLICITUD=det.IDSOLICITUD
where blo.idbloque = 1
and dia.iddia = 1
and sol.estado in(1,2)
)

Answer 2

select * from laboratorio lab1 WHERE NOT EXISTS (
select 1 from laboratorio lab
inner join DETALLESOLICITUD det on det.IDLAB = lab.IDLAB
inner join dia on dia.iddia = det.iddia inner join bloque blo on blo.idbloque = det.idbloque
inner join solicitud sol on sol.IDSOLICITUD=det.IDSOLICITUD
where blo.idbloque = 1 and dia.iddia = 1 and sol.estado in (1,2)
AND lab1.rowid = lab.rowid)
Check this out. I think you did not join with the outer table.