Re: What is metadeta?

Ryan

metadata is information that describes data.

For example metadata about an email would be a list of the fields (from, subject, date sent, to, cc etc) together with their data types (mostly strings & date)
This kind of metadata is collected to describe a data source. So a collection of metadata can be called a model. You have a model of a database(tables, relationships, columns).

Additionally some of the other information in a database describes other things about it - indexes, names of tables, organisation, security - these descriptions are also classed as metadata.

Confusingly some information stored with data can also be classed as metadata - e.g. where the data came from (loaded in batch from another database) this is because its all data in some sense - it depends upon why you are looking at it, one persons data is another persons metadata.

There are very useful whitepapers & documents at our website & you might try searching for books by adrienne tannenbaum, david marco & papers by doug laney & wayne eckerson.

Take a look at our website & see how metadata is actually crucial to key business issues for managing costs & enabling very rapid change. We use metadata (models) to drive data integration between diverse data sources - creating a unified, virtual database - often doing in days & weeks what normally takes many weeks & months. The concept of metadata has been around for ages & we follow the OMG standards so I'd recommend searching www.omg.org for references to metadata, MOF, XMI & CWM - the definitions of these are interesting.

Regards,

              David Penney
              http://www.metamatrix.com

"Ryan Gaffuri" <rkg100_at_erols.com> wrote in message news:a7ioko$849$1_at_bob.news.rcn.net...
> Dont know if this relates directly to Oracle, but I often see them
mentioned
> together?
>
>
>
Received on Sun Mar 24 2002 - 04:22:39 CST