SQL: Attribute matches two different conditions at the same time - sql

Question

I want to make a query where an attribute (same attribute) matches two different conditions at the same time. I have to check if a driver was found in both cities.
I tried to use intersect but I don't get any matches. But in my table I have one driver that matches this conditions.
SELECT s.NumeSofer
FROM Soferi s
INNER JOIN contraventii c ON s.idSofer=c.idSofer
INNER JOIN localitati l ON c.idLocContr=l.idLoc
WHERE l.DenLoc IN ('Iasi', 'Rosiori') AND l.Jud IN ('IS', 'NT');
INTERSECT
SELECT s.NumeSofer
FROM Soferi s
INNER JOIN contraventii c ON s.idSofer=c.idSofer
INNER JOIN localitati l ON c.idLocContr=l.idLoc
WHERE l.DenLoc='Rosiori' AND l.Jud='NT';

Answer 1

You can use aggregation and a HAVING clause, like:
SELECT s.NumeSofer
FROM Soferi s
INNER JOIN contraventii c ON s.idSofer=c.idSofer
INNER JOIN localitati l
ON c.idLocContr = l.idLoc
AND (l.DenLoc, l.Jud) IN ( ('Iasi', 'IS'), ('Rosiori', 'NT') )
GROUP BY s.NumeSofer
HAVING
MAX(CASE WHEN l.DenLoc = 'Iasi' AND l.Jud = 'IS' THEN 1 END) = 1
AND MAX(CASE WHEN l.DenLoc = 'Rosiori' AND l.Jud = 'NT' THEN 1 END) = 1
This will bring you all NumeSofer for which at least one record exists in localitati with DenLoc='Iasi' AND Jud='IS' and at least one record exists with DenLoc='Rosiori' AND Jud='NT'.
Note: the IN operator can be used with tuple values; this reduce the lenght of the query, while avoiding using OR, which is usually not good for general performance.

Answer 2

Do a GROUP BY instead. Use case expressions to do conditional aggregation:
SELECT s.NumeSofer, count(distinct l.DenLoc) as totcount,
count(case when l.DenLoc='Rosiori' then 1 end) as Rosioricount,
count(case when l.DenLoc='Iasi' then 1 end) as Iasicount
FROM Soferi s
INNER JOIN contraventii c ON s.idSofer=c.idSofer
INNER JOIN localitati l ON c.idLocContr=l.idLoc
WHERE (l.DenLoc='Rosiori' AND l.Jud='NT')
OR (l.DenLoc='Iasi' AND l.Jud='IS')
GROUP BY s.NumeSofer
ORDER BY totcount desc
Any rows with totcount = 2?
To get only drivers with both DenLoc's add a HAVING clause:
SELECT s.NumeSofer, count(distinct l.DenLoc) as totcount,
count(case when l.DenLoc='Rosiori' then 1 end) as Rosioricount,
count(case when l.DenLoc='Iasi' then 1 end) as Iasicount
FROM Soferi s
INNER JOIN contraventii c ON s.idSofer=c.idSofer
INNER JOIN localitati l ON c.idLocContr=l.idLoc
WHERE (l.DenLoc='Rosiori' AND l.Jud='NT')
OR (l.DenLoc='Iasi' AND l.Jud='IS')
GROUP BY s.NumeSofer
HAVING count(distinct l.DenLoc) > 1