Path: news.easynews.com!core-easynews!newsfeed3.easynews.com!easynews.com!easynews!news.glorb.com!newsfeed.utanet.at!newsfeed.wu-wien.ac.at!not-for-mail From: Michael Fuchs Newsgroups: comp.databases.theory Subject: Re: Query on a sorted list (recursive/unary relationship) Date: Sun, 06 Jun 2004 21:57:46 +0200 Organization: University of Economics and Business Administration, Vienna, Austria Lines: 19 Message-ID: References: NNTP-Posting-Host: m771p029.adsl.highway.telekom.at Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Trace: bird.wu-wien.ac.at 1086551462 4411 62.47.128.93 (6 Jun 2004 19:51:02 GMT) X-Complaints-To: abuse@wu-wien.ac.at NNTP-Posting-Date: Sun, 6 Jun 2004 19:51:02 +0000 (UTC) User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6) Gecko/20040113 X-Accept-Language: de-at, de-de, en-us, en In-Reply-To: Xref: core-easynews comp.databases.theory:35751 X-Received-Date: Sun, 06 Jun 2004 12:50:24 MST (news.easynews.com) Alan wrote: > I don't know. You never mentioned what you wanted to sort by, and I am still > not sure looking at your description. Note that you cannot order by the way > the data is stored in the table. It is a set, and by definition is not > ordered. I agree on what you say. As there is no 'natural' order, I introduced an artificial one. It is designed as a recursive relationship. The ParentID only stores the information on what node is superior. The question is not as simple as on what colum I should use the ORDER BY clause. I think I remember something like START WITH - CONNECT BY on Oracle which might do the trick. (Unfortunately I do not have Oracle but MySQL.) So are there any standard SQL workarounds for this? Thanks, Michael