相关疑难解决方法(0)

有人可以告诉我哪种方式更好,它们都能产生相同的结果,但哪种更"正确"？

我个人认为第一个查询更容易阅读,但我似乎在其他地方读到应该总是使用别名.

谢谢

SELECT Patient.PatientSurname, Doctor.DoctorSurname
FROM Patient
JOIN Operation
ON Operation.PatientCode=Patient.PatientCode
JOIN Doctor
ON Doctor.DoctorCode=Operation.DoctorCode
WHERE Operation.OperationType='Broken Arm'
GROUP BY Patient.PatientSurname
HAVING count(Patient.PatientSurname) > 0


SELECT PatientSurname, DoctorSurname
FROM Patient as p, Operation as o, Doctor as d
WHERE o.PatientCode=p.PatientCode
AND  d.DoctorCode=o.DoctorCode
AND o.OperationType='Broken Arm'
GROUP BY p.PatientSurname
HAVING count(p.PatientSurname) > 0