POSC Specifications
Version 2.3
Relational Implementation Methodology

Projection Example

This section uses a simple example to demonstrate the projection techniques described in this document. The example uses the supertype and subtype pattern of the figure that described consolidation and replication techniques. In addition, entity JJJ has been added as an abstract behavior (supertype of GGG and III) in order to demonstrate consolidating down to a subtype (III) followed by replicating up to a supertype (FFF).

Subtyping Hierarchy

The input to the process was an Express file which included the projection parameter tags in the syntax of the POSC Incremental Express Tool. For example, the tag <projmeth> specifies whether an entity should be consolidated, replicated or projected as a table. The tag <projnk> specifies whether an entity is a candidate to use a natural key for foreign keys.

Express file

Generated Oracle files


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