How to auto-increment primary key in SQL INSERT INTO statement - sql

Question

Private Sub btnAddInfo_Click()
On Error GoTo Error_Routine
'Declare variables
Dim intStudentID As Integer
Dim intTestID As Integer
Dim dblMark As Double
Dim intResultID As Integer
'Declare database
Dim db As DAO.Database
Dim rst As DAO.Recordset
'Set the database
Set db = CurrentDb
Set rst = db.OpenRecordset("Select ResultId FROM StudentResult ORDER BY RESULTID DESC", dbOpenDynaset)
'assign value to intResultID variable
intResultID = rst!ResultId
'Adds the additional 1 to the latest result id that was used
If Not rst.EOF Then
intResultID = intResultID + 1
End If
'Assigns value to variables
intStudentID = Forms!frmAdd!lstStudentID
strDescription = Forms!frmAdd!lstTest
dblMark = txtMark.Value
intTestID = Forms!frmAdd!lstTest
'Checks that Student ID has been selected
If Not IsNull(lstStudentID) Then
'Inserts new test record into StudentResult table
db.Execute "INSERT INTO StudentResult " _
& "(ResultId,StudentId,TestId, Mark) VALUES " _
& "('" & intResultID & "','" & intStudentID & "','" & intTestID & "','" & dblMark & "');"
End If
'Clears fields
txtMark.Value = ""
lstStudentID.Value = ""
lblExistingStudent.Caption = "Existing Student Name:"
'Closes database
Set db = Nothing
I'm trying to add new records. There is a list of 4 tests. ResultId is the primary key and it is an AutoNumber column.
The button adds tests scores just fine if the selected StudentID has not added a score for that TestId yet. But when I try to add a StudentId and TestId combination that has been entered before, it does not add a new record or even update the existing one.
Both StudentId and TestId allow duplicates. I've tried doing this counter variable but it has not worked. This is for a class and the professor says a student should be able to retake tests and it should just add a new record.
Thank you in advance for your help. Please let me know if you need any pictures of the form, tables, or more of my code.

Answer 1

Exclude the AutoNumber field, and don't wrap numbers in quotes:
If Not IsNull(lstStudentID) Then
' Verify values:
Debug.Print "StudentID:", intStudentID, "TestID:", intTestID, "Mark:", Str(dblMark)
'Inserts new test record into StudentResult table
db.Execute "INSERT INTO StudentResult " _
& "(StudentId, TestId, Mark) VALUES " _
& "(" & intStudentID & "," & intTestID & "," & Str(dblMark) & ");"
End If