Advanced MYSQL query dont work

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MySQL

I'm trying to run a query that looks like this:

$DB->query("INSERT INTO table (
  SELECT s.value1, s.value2, s.value3, t.value1, u.value1, u.value2, u.value3, u.value4
  FROM aTable AS s
  LEFT JOIN aTable2 AS u ON u.uID = s.uid 
  WHERE u.spent < ". $needed ."
  GROUP BY s.uid, s.fid ) 
  ON DUPLICATE KEY UPDATE
  value1 = VALUES(u.value1), 
  value2 = VALUES(u.value2), 
  value3 = VALUES(u.value3), 
  value4 = VALUES(u.value4);
");

However this returns the error:

Unknown column 'u.value1' in 'field list'

Please note that this is the first time I'm working with MySQL at this level, so I have no idea how the DUPLICATE KEY UPDATE function works...

What i intent to do with the table is like a cache, because the infromation is fetched from some very large table