JOIN three tables

Question

I am trying to retrieve two sets of information (the red and blue portions of the diagram in the one query.

I thought I could do it using the sql as stated below but

Answer 1

try something like this

SELECT A.* FROM TableA A
LEFT OUTER JOIN TableB B ON (A.id = B.a_id)
LEFT OUTER JOIN TableC C ON (A.id = C.a_id)
WHERE B.a_id IS NOT NULL 
  OR c.a_id IS NOT NULL