teacher table
teacher_id teacher_name
============================
1 john
2 doe
student table
student_id student_name student_score teacher_id
==========================================================
1 amelia 0 1
2 anderson 0 1
3 fabiano 0 1
4 ronaldo 0 2
5 peter 6 2
6 alex 0 2
result
teacher_id teacher_name
============================
2 doe
the result is teacher record who one or more of his student score > 0.
How the query of this ?
thanks for the answer and sorry for my bad english
A simple subquery does the trick
SELECT * FROM teacher WHERE teacher_id IN
(SELECT teacher_id FROM student WHERE student_score > 0)
Also possible is an INNER JOIN
SELECT teacher.* FROM teacher
LEFT JOIN student as student teacher.teacher_id = student.teacher_id
WHERE student.student_score > 0
Hopefully this will works for you.