However, managing large amounts of metadata as repositories are updated and replicated can become an overwhelming task. IRDL can be used to impose logical structure on repositories of physical data, to maintain and distribute repository structure across locations, and to define new methods for accessing arbitrarily formatted data. 2.0 Overview IRDL is a data modelling language which was originally designed to control the metadata generation process.
IRDL programs can serve as a blueprint for the logical structure of a repository.
From the perspective of metadata evolution, as raw data changes over time, the metadata representation must also evolve to maintain consistency. As shown in Fig. 1, existing IRDL programs can simply be reinterpreted with the new data to create a new repository with the same logical structure. In effect, it is possible to generate logical structures shared by any community or organization operating in a distributed environment. Maintenance of Information Repositories. This support is conditional on the availability of the appropriate types libraries that may be created either independently or by interpreting the type definition statements.