Multiple INNER JOIN from the same table
You should specify different aliases for your tables . you are calling all of them m.
SELECT m1.MetalCode as 'Metal1', m2.MetalCode as 'Metal2',m3.MetalCode as 'Metal3'FROM Item as kINNER JOIN Metals AS m1 ON m1.metalID=k.metal1 INNER JOIN Metals AS m2 ON m2.metalID=k.metal2INNER JOIN Metals AS m3 ON m3.metalID=k.metal3WHERE k.ItemID=?
Well, not completely wrong. ;)
Wherever you have "INNER JOIN Metals AS m", m needs to be something unique (not m every time).
Try something like this (not tested):
SELECT m1.MetalCode as 'Metal1', m2.MetalCode as 'Metal2', m3.MetalCode as 'Metal3'FROM Item as kINNER JOIN Metals AS m1 ON m1.metalID=k.metal1 INNER JOIN Metals AS m2 ON m2.metalID=k.metal2INNER JOIN Metals AS m3 ON m3.metalID=k.metal3WHERE k.ItemID=?
try this:
SELECT m.MetalCode as 'Metal1', n.MetalCode as 'Metal2'o.MetalCode as 'Metal3'FROM Item as k INNER JOIN Metals AS m ON m.metalID=k.metal1 INNER JOIN Metals AS n ON n.metalID=k.metal2 INNER JOIN Metals AS o ON o.metalID=k.metal3WHERE k.ItemID=?