UML_Anotated 1 - UML has a number of advantages over its...

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UML has a number of advantages over its predecessors: 1) A constraints between relationships in the Barker notation is replaced by a simple line between two associations that can be annotated to describe any relationship between two associations. The Barker constraints between relationships is represented in the UML by the word "or", but other inter- association relationships may be represented that the Barker notation cannot represent. This is useful for introducing many kinds of business rules. 2) For business rules that are not simple relationships between two associations, the UML introduces a small flag that can include text describing any business rule. 3) Attributes can be described in more detail than in other notations. 4) The UML approach to optionally and cardinality makes it possible to express more complex upper limits, as in "each <entity 1> may be related to zero, 3, 6-7, or 9 occurrences of <entity 2>". 5) Overlapping and incomplete configurations of sub-types are allowed. 6) Multiple inheritance and multiple type hierarchies are permitted. http://www.essentialstrategies.com/publications/modeling/uml.htm
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UML: Advantages • Forces planned approach to schema changes rather than un documented changes made in ArcCatalog • Schema is fully portable and easily shared with other organizations • Single document that shows current state of the database • Allows schema development while work on the database continues
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UML_Anotated 1 - UML has a number of advantages over its...

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