Query Perspective (Spider)

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Doradus Query Language: Query Perspective

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A DQL instance is a Boolean expression that selects objects from a perspective table. Logically, the query expression is evaluated against each perspective object; if the expression evaluates to "true", the query selects the object.

The query expression may include clauses that reference fields from objects that are linked to a perspective object. For example, if the perspective table is Person, the clause Manager.Name:John is true if a person’s Manager points to an object whose Name field includes the term John.

In object queries, requested fields are returned by the query for each selected perspective object. In aggregate queries, selected objects are included in one or more metric computations.