SQL Select-streng virker ikke

Din forespørgsel er forkert:Prøv dette

SELECT Comment1, Comment2, Comment3, Comment4 
FROM Students 
WHERE Course1 = '$value1' AND Course2 = '$value1' 
AND Course3 = '$value1' AND Course4 = '$value1'

ELLER

SELECT Comment1, Comment2, Comment3, Comment4 
FROM Students 
WHERE Course1 = '$value1' OR Course2 = '$value1' 
OR Course3 = '$value1' OR Course4 = '$value1'

Baseret på dit krav, brug OG eller ELLER, mens du tjekker kurset