Data Items (Magic xpa 4.x)
Data items are the building blocks of any data structure. They are usually called columns or variables, because they are physically stored in data sources.
Magic xpa data items are:
Columns – Components of data table rows that hold actual data values. You define the columns for a project in the Data repository. When several different columns have the same characteristics, you can define a field model for them in the Model repository. For more information about defining columns and field models, see Models and Data Sources.
Virtual Variables – Local variables used by a Magic xpa task for computation and temporary storage. You define the Virtual variables you need when you define the task. You can also use the field models you predefined in the Model repository. The Virtual variable exists only for the program duration, so its value is not saved after the program execution is terminated. This means that in each execution, the values of the variables return to their default values.
Parameter Variables – Local variables designated to receive values from a called task or program.
Data items are defined in terms of Attributes and Pictures, as well as other optional properties, such as Ranges.
Form Models
Control Models
