Adding and Deleting Fields in Views	Contents
	*Enhancing the Data Model with Type Information
	Creating a View for a Root

Note: Fields are the different kinds of data that is filled from your database. A field may be a number, an image, or simply text. These are called primitive or literal fields because they contain only one value. However a field may also be composed of several values. The type of such composite fields is either a class or a collection. In many respects (e.g. adding, moving, deleting, naming) composite fields behave just like literal fields. However they are configured differently from literal fields.

Icons of fields

The different kinds of fields are indicated by icons:

Number
Text (String)
Boolean (Yes/No)
Formula
Total (sum, min, max, average)
Class reference or 1:1 relationship (in the source tree)
Class View (Sub view in the view tree)
Collection
Grouped Collection

Adding Fields

To add a field:

Just drag it from the source tree to the view tree. It will be added under the currently selected element. (In alphabetical order.) If you drag an element from a related class or table, then a path field will be generated. After dropping it, you can select it and edit the properties (e.g. rename the field)

Path fields are a useful technique to simplify the data model for the report designer. All relevant fields will be concentrated in one view, and the underlying normalized structure of the classes/tables can be hidden. If you do not want to hide the structure then you can use nested views instead.

Note: The sequence of fields in a view is not relevant. Therefore fields are shown in alphabetical order.

Editing Properties of Literal Fields

Source

The source field where the value will be taken from. This is an informational field which cannot be edited.

Member Name

The name for this field. Click in the value column to change the name. It is recommended to use a programming laguage compatible identifier as the name. Then you can use this name in query expressions witout quoting it.

Fields with Nested Views

If you add a class typed field to the view then this becomes an nested view.

1. The nested view is shown as new subbranch in the view tree.
2. The fields tree of the structure pane changes to show the fields that are available for the nested view.
3. The property page shows the properties of the nested view.

Note:The list of fields always shows exactly the list of fields that are reachable for your view. You cannot directly add fields from the enclosing type or view. (If you do need it, you can use a formula with the from() built in function. In object models with inheritance, you may need to enhance the data model with a cast (see sub type below).

Properties of Nested Views

Source

This is the field where data comes from. This is an informational field, that cannot be changed.

Member name

The name how your nested view appears in the view that contains it. You can edit this to provide a name that is meaningful to the user.

Type View

The type name of your view. Usually, you do not need to care about the name that appears there. However if you want to reuse this subview in other places (other views, that refer to the same class) you can give the subview a name. This name can then be retrieved by pressing the ellipes button, which will bring up a list of views for that type.

Subtype

When you are dealing with object models, that use inheritance, then sometimes a class typed field is declared as the base class of the actual type. You can switch to one of the subtypes of the declared type, so that all the fields of this type are shown. This is explained in detail in the chapter on casting.

Creating a View for a Root

Contents

*Enhancing the Data Model with Type Information