Views are a powerful means to deal with complex databases. They are usually set up by developers to simplify the task of database designers.
serve to simplify access to the database classes and to enhance the data model. They are also used to control access to data and to define specific xml mappings.
Database classes can contain many fields that are not relevant to a certain reporting task. A class can contain implementation oriented fields like the getClass field or fields that are only for indexing. Such fields confuse end users and make it harder to create reports. Sometimes fields that you want in your report are not directly in the class, but in a related class that is only accessible by traversing a link (navigating).
ReportWeaver uses the schema information in your database to present you with the fields that can be used in a report. The schema contains information about the types (classes, relational tables) in your database and how they are connected to each other via links (references, foreign keys). Sometimes this information might be incomplete. In order to build a template ReportWeaver needs a complete schema information which must be supplied by you.
The most frequent situations when schema enhancement is needed are:
In order to deal with these situations views must be created.
Not all fields and objects may be shown to everybody.
When exporting to XML you may want to target a specific DTD/XML-Schema. To achieve this fields and objects must be mapped to specific tags.
|Interactive Data Selection||Contents||Creating a View for a Root|