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RE: is-collection - isdefined

From: Wallmer, Martin <Martin.Wallmer@softwareag.com>
Date: Wed, 27 Mar 2002 08:24:35 +0100
Message-ID: <DFF2AC9E3583D511A21F0008C7E6210602D9006B@daemsg02.software-ag.de>
To: "'Jim Whitehead'" <ejw@cse.ucsc.edu>, "Wallmer, Martin" <Martin.Wallmer@softwareag.com>, www-webdav-dasl@w3.org

currently the contains operator is not yet implemented as well as some minor
;-) things like "like", "limit", "nresults", I18N issues not yet tested. But
will follow soon (hopefully). QSD is also missing.

I do not have experience with efficiency yet, but I don't expect that the
performance is very good with this implementation. The plan is as follows:

Slide can support several stores, filestore, SQL database or whatever. Of
course searching can be done most efficiently by the database, SQL, XQuery,
... But if you say, that slide is DASLabled, SEARCH should work for any
store. So this implementation as the first step is very generic and does the
search in the slide kernel. That means, make a kind of PROPFIND and filter
the nonmatching out. This SEARCH mechanism can be overwritten with efficient
SEARCH methods by the specific store. Also parts of the generic
implementation may be used. Imagine a store, that uses an SQL database for
the properties and the file system for content. This store may overwrite the
searching on the properties but use the "contains" operator of the generic

Our next major step will be to implement the SEARCH methods for our Tamino
store (http://www.softwareag.com/tamino/, Tamino WebDAV Server).

The problem you mentioned with dead properties is a "relational" problem
(the well defined live properties are columns, perhaps indexed, but the
customer defined dead properties must be rows in another table, you need
tricky joins). In XML, dead or live properties are just properties, the
XQuery search engine can handle this very efficiently. 


-----Original Message-----
From: Jim Whitehead [mailto:ejw@cse.ucsc.edu]
Sent: Dienstag, 26. März 2002 19:19
To: Wallmer, Martin; www-webdav-dasl@w3.org
Subject: RE: is-collection - isdefined

> there is a first DASL prototype in the current Slide
> (http://jakarta.apache.org/slide/index.html) (not yet released, not yet
> mentioned in the Slide docu). It follows the new draft.

This is good to hear! How much of the current draft do you implement? Also,
how do you handle the tricky issue of efficiently searching over
client-defined dead properties?

- Jim
Received on Wednesday, 27 March 2002 02:24:40 UTC

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