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Defaults

Default properties can be set to simplify queries. Once a default is set, that value is used for the property in all subsequent operations. Properties specifically mentioned in an operation override their default values. The syntax for setting defaults is straightforward. Below is an example that retrieves movie stars' names that are current in the semi-structure.

SET DEFAULT PROPERTY
    (TRANSACTION_TIME: [now-now]);
SELECT movie.star.name;
Security is one of the most common default settings. Users can advertise their security certificates in all subsequent queries by setting a default.
SET DEFAULT PROPERTY 
    (SECURITY: over 18 AND subscriber);




Copyright © 1998. Curtis E. Dyreson, Michael H. B&. All rights reserved.