Oracle® Application Development Framework Developer's Guide
10g Release 3 (10.1.3) B25386-01 |
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To query objects, you can create a TopLink Named query then create a data control for the class specified in the query. This will expose the TopLink query to the data control.
A named query is a TopLink query that you create and store for later retrieval and execution. Named queries improve application performance because they are prepared once and they (and all their associated supporting objects) can be efficiently reused thereafter making them well suited for frequently executed operations.
You can create the following queries:
ReadAllQuery
ReadObjectQuery
A query by example enables you to specify query selection criteria in the form of a sample object instance that you populate with only the attributes you want to use for the query. To define a query by example, provide a ReadObjectQuery
or a ReadAllQuery
with a sample persistent object instance and an optional query by example policy.
With ADF, a TopLink query by example performs only in-memory querying.
You cannot configure the sort criteria of a TopLink query from Oracle JDeveloper. You must write a Java method, using descriptor amendment method. See Section 3.3.3.2, "Using Amendment Methods" for more information.