How can I write a calculation field in a table that outputs '1' if there are other (related) records in the same table that meet a given set of criteria and '0' otherwise?
I have a table containing 'students' and another containing 'exam results'. The 'exam results' table looks like this:
StudentID SubjectID Level Result
3234 1 2 A-
3234 2 4 B+
4739 1 4 C+
A student can only pass a Level 4 exam in subject 2 if they have also passed a Level 2 exam in subject 1 with a B+ or higher. I want to define a field in the 'students' table that contains a '1' if there exists an exam result belonging to the right student that meets these criteria and a '0' otherwise.
What would be the best way to do this?
Let us take an example of a Results table where the results are also calculated as a numeric value, e.g.
StudentID SubjectID Level Result cResultNum
3234 1 2 A- 95
3234 2 4 B+ 85
4739 1 4 C+ 75
and an Exams table with the following fields (among others):
Given these, you can construct a relationship between Exams and (another occurrence of) Results as:
Exams::RequiredSubjectID = Results 2::SubjectID
AND
Exams::RequiredLevel = Results 2::Level
AND
Exams::RequiredResultNum ≤ Results 2::cResultNum
This allows each exam record to calculate a list of students that are eligible to take that exam as =
List ( Results 2::StudentID )
I want to define a field in the 'students' table that contains a '1' if there exists an exam result belonging to the right student that meets these criteria and a '0' otherwise.
This request is unclear, because there are many exams a student may want to take, and a field in the Students table can calculate only one result.