Path: news.f.de.plusline.net!news-fra1.dfn.de!news-stu1.dfn.de!news.germany.com!postnews.google.com!news3.google.com!news.glorb.com!feed.cgocable.net!pd7cy1no!pd7cy2no!shaw.ca!pd7urf3no.POSTED!53ab2750!not-for-mail X-Trace-PostClient-IP: 24.84.208.66 From: paul c User-Agent: Mozilla Thunderbird 1.0.7 (Windows/20050923) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.databases.theory Subject: Re: A new approach to storing ordered hierarchical data in RDBs. References: <1164123446.259556.120310@h54g2000cwb.googlegroups.com> <1164128220.823492.151280@m7g2000cwm.googlegroups.com> <1164146319.099192.127130@h48g2000cwc.googlegroups.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Lines: 35 Message-ID: Date: Wed, 22 Nov 2006 00:40:11 GMT NNTP-Posting-Host: 64.59.144.74 X-Complaints-To: abuse@shaw.ca X-Trace: pd7urf3no 1164156011 64.59.144.74 (Tue, 21 Nov 2006 17:40:11 MST) NNTP-Posting-Date: Tue, 21 Nov 2006 17:40:11 MST Organization: Shaw Residential Internet Xref: news.f.de.plusline.net comp.databases.theory:40123 paul c wrote: > Lennart wrote: > >> Aloha Kakuikanu wrote: >> [...] >> >>> Please make sure you use terms correctly. What you have meant by >>> "lineage" is "transitive closure". This article >>> http://www.sqlteam.com/item.asp?ItemID=8866 >>> uses the term "lineage" in the sense of "materialized path". >> >> >> >> I especially liked the phrase "Don't worry about the loop" :-) >> >> /Lennart >> > > I especially laughed at the phrase "XML handles hierarchical ... quite > well". How the dickens does XML per se calculate transitive closure or > depth from an adjency list or an adjaceny list from a tree? It seems to > me that XML by itself only allows adhoc solutions that are just as > non-declarative as various SQL versions. For that matter, the original > relational model seems to requires similar adhoc additions. I don't > have a solution, but it seems to me that all three are lacking and it is > irresponsible, ignorant and cavalier to use the adverb "well" regarding > accomplishing closure with any of them. > > p sorry about the spelling, mine is going down-hill as fast as my opinions are ossifying, i guess it should be adjacency but sooner or later some marketing type will spell it 'agency list'. p