[phpPete]

I have, lets say two tables, one Course, and the other Student.

Table: Course
Attributes: CourseID
StudentID

Table: Student
Attributes: StudentID
Name

How do I prevent the student from being able to register for more than 10 classes?

[MattR]

You would have to perform a query in your application beforehand since MySQL does not support constraints.

e.g.

LOCK TABLE course
SELECT COUNT( * )
  FROM course
 WHERE studentid = $someid

IF count > 9
  echo "no!"
ELSE
  INSERT
UNLOCK TABLE course