Re: Modelling hierarchy in the relational database
Date: Fri, 17 Aug 2001 18:38:43 -0400
Message-ID: <3b7d9b0b_3_at_news3.prserv.net>
Assuming you are using SQL Server, check out the section "Expanding Hierarchies" in the SQL Server Books Online.
You might also consider checking out "Advanced Transact-SQL for SQL Server 2000" by Itzik Ben-Gan and Tom Moreau for discussion and code related to modeling a hierarchical structure in a relational database.
Similarly, "SQL for Smarties" by Joe Celko has discussion and code related to modeling a hierarchical structure in a relational database. Joe's method is different from that in the book by Itzik and Tom. Joe's code is not SQL Server specific, but ANSI SQL-92, and so will require some changes to work in SQL Server.
BP Margolin
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"abracad" <abracad_at_nospam.com> wrote in message
news:3b7d87c0.509669_at_news.freeserve.net...
> I am constructing a database to model hierarchy, e.g.
> A
> |
B
> |
> C
>
> I envisage a table parent consisiting fields parent, child and would
> store records A,B and B,C. Would I also need to store record A,C?
>
> I.e. can SQL act recursively to determina all the children of a given
> node (could it retrieve B and C if I queried for the children of A
> with only records A,B and B,C stored?)
>
> Many thanks in advance for any help on this
Received on Sat Aug 18 2001 - 00:38:43 CEST