Sourcing Metadata for Database Independence

From: Dawn M. Wolthuis <dwolt_at_tincat-group.comREMOVE>
Date: Sun, 8 Aug 2004 14:08:31 -0500
Message-ID: <cf5top$999$1_at_news.netins.net>



For database independent applications, such as those written by many application software development companies, the most basic of metadata, such as the names of attributes, must be sourced so it is useful with any target database implementation. There are many different strategies for where to source such metadata (as well as how extensive this metadata should be since all code is, itself, metadata).

It could be sourced in code, thereby fixing on a particular language while remaining database-independent. It could be sourced in the metadata repository of a development database from which the product is built for any environment. It could be sourced in XML documents (or any type of parm file) that serve as input for the code and for the database processes. It could be sourced as data in a database (rather than simply as metadata). This could be an embedded database in a metadata service.

If you figure that the specification of a data type for a given attribute is a business rule, of sorts, you could have a business rules repository that is the source of all metadata. You are then tied to a particular rules engine (which might then tie you to a language or database too) even if it is written in-house. I know there are some not-very-widely-used standards for metadata repositories -- are there industry standards for rules specifications other than SQL? There are also third party metadata repositories.

I'm thinking more about the future than about what are the currently most accepted practicies. If you are not tied to a specific language or database up front and are developing a new software application to be deployed at many customer sites on many different databases, where/how would you source the metadata? Thanks in advance for your thoughts on this.. --dawn Received on Sun Aug 08 2004 - 21:08:31 CEST

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