The conceptual schema and external schemata of metadatabases

摘要

We consider statistical databases. They consist of three layerswhich refer to micro-, macro- and metadata. Metadata are viewed as dataabout micro- and macrodata. Metadata have non-standard characteristics,i.e. they are not fixed formatted, are highly cross-referenced and areextremely heterogenous. This is especially true for the underlying datastructures and the set of operators needed for data definition,manipulation and control. Moreover, data integrity and confidentialityneed special attention. We focus on the conceptual design of metadataand consider different user view's in some detail