Clear Separation of Semantics and System-specific Constraints
Because metadata registries are used to store both semantics (the meaning of a data element) and systems-specific constraints (for example the maximum length of a string) it is important to identify what systems impose these constraints and to document them. For example the maximum length of a string should not change the meaning of a data element.
The International Organization for Standardization (ISO) has published standards for a metadata registry called ISO/IEC 11179 and also ISO15000-3 and ISO15000-4 ebXML registry and repository (regrep) EbXML RegRep
Read more about this topic: Metadata Registry
Famous quotes containing the words clear, separation and/or constraints:
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Knows no discord,
But still moves delight,
Like clear springs renewed by flowing,
Ever perfect, ever in them-
Selves eternal.”
—Thomas Campion (1567–1620)
“In a separation it is the one who is not really in love who says the more tender things.”
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“The analogy between the mind and a computer fails for many reasons. The brain is constructed by principles that assure diversity and degeneracy. Unlike a computer, it has no replicative memory. It is historical and value driven. It forms categories by internal criteria and by constraints acting at many scales, not by means of a syntactically constructed program. The world with which the brain interacts is not unequivocally made up of classical categories.”
—Gerald M. Edelman (b. 1928)