ActiveReports Server now supports two methods for reports to access data: Shared Data Sets and Data Models. The obvious question then is which should you use? To answer that question, we need to understand what types of reports you are serving up using ActiveReports Server. With ActiveReports Server, you can serve up two types of ActiveReports to your users:
So the answer to our question is this: RDL and Page reports can take advantage of our new shared data sets feature, while the Semantic reports created using the web-based Designer add-on always use data models to access data. Both of these server-based data access methods enable the administrator to govern the data that is available to report authors.
A data model is a construct that organizes data from your data source into entities, and defines relationships between them. Each entity has its own set of attributes. When you create a data model in the Administrator Dashboard, you provide connection information, and the wizard walks you through selecting tables and views, and it sets up relations automatically. You can go back and fine tune the details, and set up role-based permissions for each model. Your users select a data model from a list of ones to which they have permissions, and then use it as a basis for creating reports. When these reports are executed, the query is generated dynamically and sent to the database to retrieve the data.
A shared data set retrieves data fields from a shared data source using a query defined at the time of the creation of the shared data set. When you create a shared data set in the ActiveReports Designer (either in Visual Studio or in an End User Designer application), it allows you to add calculated fields, parameters, filters, and other options. This gives report authors a flat table structure, or query result set, for use in their reports. Your developers and users can use these data sets in multiple Page or RDL reports, and if you need to make a change, you can do it in one place instead of changing each report. Learn more about shared data sets in Why Care About Shared Data Sets?