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oracle adf workshop


Linking View Objects

You have learned to use associations to define a relationship between entity objects. You have also learned how to join multiple tables in a view object query, producing a single view object that contains attributes from multiple tables. View links enable you to join multiple view objects in a master–detail hierarchy. When your needs call for showing the user a set of master rows, and for each master row a set of coordinated detail rows, then you can create view links to define how you want the master and detail view objects to relate. Note, however, that a query of the detail view object via the master only occurs as long as the view link is included as part of the application module.

To define a view link, you can first create a view object that queries on the master table and another that queries on the detail table. Then you can create a new view link, selecting the attributes of the source (master) and destination (detail) view objects to link on and clicking Add to create the source/destination pair. If there are multiple attribute pairs required to define the link between master and detail, you can repeat these steps to add additional source/destination attribute pairs.