DXL attributes and layout DXL columns
Both DXL attributes and layout DXL columns use DXL programs to calculate values that are displayed in the module. DXL programs can calculate the number of days since an object was last modified, or the number of in-links and out-links that an object has.
The differences between DXL attributes and layout DXL columns are subtle.
With DXL attributes, the DXL program is associated with an attribute definition. You can use the attribute in multiple columns and in multiple views.
With layout DXL columns, the DXL program is associated with a single column, but not with any attribute. A layout DXL column is a column that does not contain an attribute. Instead, it uses the DXL program to calculate what to display.
The values of DXL attributes are automatically calculated when the object is first displayed on your screen. To make Rational® DOORS® recalculate the values, click Tools > Refresh DXL Attributes. The DXL programs run in the background, and the values are updated.
The values in layout DXL columns are automatically recalculated whenever Rational DOORS refreshes your screen. If the DXL program that is associated with the column is computer intensive, the constant recalculation of the values can lead to poor performance. In this case, consider using a DXL attribute instead of a layout DXL column.
Use attribute DXL, or convert your layout DXL column to attribute DXL, if the column contains a large amount of data. You cannot scroll layout DXL if the object contains more data than can be displayed on the screen, but you can scroll attribute DXL.
For more information, see the DXL attributes section of the DXL Reference Manual. The manual is available the Help menu in Rational DOORS. Click .