Re: [T] S.O.D.A. --> Relational GUI
Date: Mon, 23 Jul 2001 02:54:51 GMT
Message-ID: <%lM67.394616$p33.7952462_at_news1.sttls1.wa.home.com>
> > Sure, SQL isn't going to be able to handle the nested guis (the BOM
problem)
> > though.
> >
>
> I keeping seeing variations of this. Note that:
>
> 1. SQL may not *by itself* be capable of everything.
> I have used procedural recursion in conjunction with
> SQL to get nested (tree) structures.
>
> 2. There are vendor-specific "tree commands" available
> in some SQL dialects. Please be clear about whether
> you are picking on existing systems (and which one)
> or a paradigm's fundimental limitations.
Another portable approach is to "explode the BOM" and treat each level of the hierarchy as a set that contains the elements below. This adds many more rows, but SQL can work pretty well with set-based queries as opposed to tree-based queries.
-- Patrick Logan mailto:patrickdlogan_at_home.comReceived on Mon Jul 23 2001 - 04:54:51 CEST