* = Problems encountered when converting to LEFT OUTER JOIN

wallace777

Questions are as follows:
My table A B is now outreach and they all have 3 columns COL1, COL2, COL3

The conditions at * = are
SELECT A. *, B. * FROM A, B WHERE A.COL1 + A.COL2 + A.COL3 * = B.COL1 + B.COL2 + B.COL3
How do I write a LEFT OUTER JOIN? Thank you!
Don't know if i understand

leon1leon1

Direct LEFT OUTER JOIN to see if it can be achieved
SELECT
  COL1
  FROM A LEFT OUTER JOIN B
     ON A.COL1 = B.COL1
       AND A.COL2 = B.COL2
       AND A.COL3 = B.COL3