Performance-issues using View Accessors and List of Values : The default behavior of the JDeveloper and ADF has a negative effect on the performance of your application with LOV's. For many cases we are showing some components as select one choice i.e. LOV which will be based on some VO.For that we create ViewAccessors. ex. Above screen shows the attribute(Descri) on which LOV is made with SomeVo. Suppose we have to define LOV in EmployeeVO on department_id attribute.For that we have to create one DepartmentVO and EmployeeVO. We will create 1 ViewAccessor for DepartmentVO based on department id in EmployeeVO. If you drag this EmployeeVO on your page you can see that executeQueryForCollection is called only once for EmployeeVO but for multiple times it is called for DepartmentVO. The query to determine the choice-list values for the DepartmentId is executed for every row in the EmployeeView. This is unnecessary and can have the performance impact of your app
Advanced ADF and Webcenter Learning