Re: XML or a relational Database ?

On Mon, 5 Mar 2001, Leonardo B Lopes wrote:

> Carlos Bromanski wrote:
> >
> > We're veering off topic! Yee haw!
> > When you say "access most of your data sequentially", do you mean that in
> > any process that needs data, you always start at the beginning of the data
> > set and read through it to the end? I don't get it.
>
> That is what I mean, _most_ of the time
>
> > What about ordering, selecting, combining, summarizing, or comparing data
> > from various subsets of the database? It's insane to perform those kinds of
> > operations with only sequential access.
>
> I don't need to perform those.
>
> > And memory management IMHO is totally separate from databases. Confusing or
> > mingling the two means trouble. I take it for granted.that my database
> > software has MM built in.
>
> That is why I am currently using an RDB. But I am conscious that I am
> killing a mosquito with a bazooka and carrying the bazooka around. If
> the XML library handles memory well, it might be more appropriate. Akmal
> mentioned streaming. But when I search for streaming in the MySQL manual
> I get nothing. So I don't know if it is not available there, or maybe
> has another name... That might reduce my performance penalty.

Leonardo, I didn't realise you were using MySQL.

A couple of other sources I can suggest on XML and DBs, with particular relevance to RDBs:

http://www.xml-und-datenbanken.de/

Some of the research is in German. These researchers have looked at document storage using Informix and DB2. Another way to get better performance is change the structure of the XML storage:

D. Florescu and D. Kossmann (1999) A performance evaluation of alternative mapping schemes for storing XML data in a Relational database. Technical Report No. 3680, INRIA, Le Chesnay Cedex, France, May 1999.

http://www-rodin.inria.fr/dataFiles/FK99.ps

If I think of anything else, I'll post it you.

Take care.

>
> > - cb
> >
> > Leonardo B Lopes <leo_at_iems.nwu.edu> wrote in message
> > news:3AA000D6.B1161103_at_iems.nwu.edu...
> > > DISCLAIMER: Just throwing ideas up in the air. I'll read the two papers
> > > Carlos and Akmal mentioned, and maybe change my view, but here it goes:
> > >
> > > How about the case in which you access most of your data sequentially,
> > > you write once but read many, there are a lot of data and you don't want
> > > to deal with Memory Management issues? That is the situation I am in
> > > now, and I am using an RDB to get around the MM. But the XML libraries
> > > (I naively assume) have pretty sophisticated MM built into them, so that
> > > may be an option.
> > >
> > > Florian Barbera wrote:
> > > >
> > > > Hi !
> > > >
> > > > what would you be, according to you, the situation where you would use
 XML
> > > > files (with a XML server if we need it) instead of a relational Database
 ?
> > > >
> > > > Thanks !
> > > >
> > > > Florian
> > >
> > > --
> > > =======================================================================
> > > Leonardo B. Lopes leo_at_iems.nwu.edu
> > > Ph.D. Student (847)491-8470
> > > IEMS - Northwestern University http://www.iems.nwu.edu/~leo
>
> --
> =======================================================================
> Leonardo B. Lopes leo_at_iems.nwu.edu
> Ph.D. Student (847)491-8470
> IEMS - Northwestern University http://www.iems.nwu.edu/~leo
>
>

--
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[ http://www.soi.city.ac.uk/~akmal/ ]