Re: SQL3 UNDER
Chris Bitmead <chris@bitmead.com>
From: Chris Bitmead <chris@bitmead.com>
To: "Robert B. Easter" <reaster@comptechnews.com>
Cc: pgsql-hackers@postgresql.org
Date: 2000-05-23T09:16:56Z
Lists: pgsql-hackers
> I'll try to provide examples later. For now, did you see the gif > attachments on a earlier message of mine? I didn't before, but I do now. > The UNDER and CLONES/INHERITS gif pictures > provide a graphical view of what I mean. UNDER creates tree hierarchy > down vertically, while INHERITS supports multiple inheritance in a > lateral direction. The UNDER trees can be under any table that is part > of an INHERITS relationship. UNDER and INHERITS work at different > levels sorta. A subtable in an UNDER hierarchy can't be in an INHERITS > clause because it is logically just part of its maximal supertable. In > other words, INHERITS can provide a relationship between different > whole trees created by UNDER, by way of a maximal supertable being > inherited by another maximal supertable with its own > UNDER tree. Make any sense? :-) I'm afraid not. Show me the (SQL) code :-).