JOIN not working with PHP + ODBC + Microsoft Access - php

Question

I am trying to write a PHP script that plugs into an existing Access Database. If I would be starting from scratch, I would have used MySQL for the job, but because there is an existing MS Access application I am stuck with the database as it is.
As of right now, I am trying to get the following PHP Code to work.
$conn=odbc_connect('buju','','');
if (!$conn)
{
exit("Connection Failed: " . $conn);
}
$sql="SELECT *
FROM Teilnehmer
INNER JOIN TeilnWerte ON Teilnehmer.LfdNr = TeilnWerte.Teilnehmer
WHERE Teilnehmer.Klasse = '$_POST[klasse]'";
$rs=odbc_exec($conn,$sql);
echo "\nErrorCode:\n".odbc_error($conn);
echo "\nErrorMessage:\n".odbc_errormsg($conn);
I am pretty sure, that the problem is in the SQL Query, since it all works fine if I only do
SELECT * FROM Teilnehmer WHERE Klasse = '$_POST[klasse]'
without trying to join the second table.
I am using odbc and the Microsoft Access Driver. The Error Code that I get is 07001. The Error Message is
[Microsoft][ODBC Microsoft Access Driver] Too few parameters. Expected 1.
I have also tried
SELECT *
FROM Teilnehmer, TeilnWerte
WHERE Teilnehmer.LfdNr = TeilnWerte.Teilnehmer
AND Teilnehmer.Klasse = '$_POST[klasse]'
which did not work either.
Is there anything that I am doing wrong? Are there certain SQL commands that don't work

Answer 1

Since echo $sql gives you ...
SELECT *
FROM
Teilnehmer
INNER JOIN TeilnWerte
ON Teilnehmer.LfdNr = TeilnWerte.Teilnehmer
WHERE Teilnehmer.Klasse = '06A'
Test that same statement as a new query in Access. Create a query in the query designer, switch to SQL View, paste in the statement and see what happens when you run it.
Most often the cause of "Too few parameters" is a misspelled item (object name, function or SQL keyword). Since the db engine can't find that item, it assumes the item is a parameter. Access will pop up a parameter dialog asking you to supply a parameter value, and that dialog also contains the parameter's name. So it tells you which is the misspelled item.