Adding and managing views
RISE supports creation of views. These views results, when generating relational database code, in SQL views. The purposes of a RISE view are to:
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Combine an information structure into a single list of higher level objects, i.e. flattening out a structure.
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Apply a filtering condition to generate a subset of an entity or another view
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Combinations of purpose 1 and 2.
Views in RISE automatically joins entities and views along defined relations in a model. RISE does not support building views based on other join criterias than the existing relations. Thus, a view is built according to the following schema:
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Pick a base entity for the view (corresponds to the SQL FROM table).
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For each extension to the base entity (corresponds to SQL JOIN).
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Select a relation starting at base entity.
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Pick one of the objects (entity or view) found at the other end of the relation.
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Select any number of attributes of the selected object.
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Optionally, specify that the extension is mandatory (corresponds to an INNER JOIN).
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Specify the filterings criterias for the view (corresponds to the WHERE clause).
As indicated by step 2.4 above extension objects are allowed to be non-existant by default, i.e. LEFT OUTER JOIN.
