Some SQL Help Please

Given a DB structure some like a tree:

                    A


                    |

                    B -- C


                    |

                    D


                    |

               F -- E


                    |

               G -- H -- I

I issue a select like:
SELECT A.colx, B.colx, C.colx, D.colx, E.colx, F.colx,

       G.colx, H.colx, I.colx

FROM A, B, C, D, E, F, G, H, I WHERE A.key = B.key AND C.key = B.key AND D.key = C.key

      AND E.key = D.key AND F.KEY = E.key AND H.key = E.key
      AND G.key = H.key AND I.key = H.key;

How do I make this work if all tables do not contain data for all records. For example, A, B, D, E, F, and H have data but other tables (G and I) do not.

How do I get all data except for those tables (Leaving G.colx and I.colx) null in the response?

Hope this makes sense. Received on Sun Jun 13 2004 - 20:59:19 CEST