Customizing the metamodel : Keywords for USRPROPS : COUNT_FIXED
  
COUNT_FIXED
The COUNT_FIXED keyword is used with the ASGRID keyword to specify that the user cannot delete or insert rows to a grid. The number of rows is fixed.
Example
DEFINITION "Association"
{
BROWSER { OMITKEY }
LAYOUT { COLS 1 ALIGN OVER TAB }
CHAPTER "Roles"
PROPERTY "Association GUID" { KEY EDIT Text LENGTH 64 INVISIBLE READONLY}
PROPERTY "Class Roles" { EDIT COMPLETE ListOf "Association
End" KEYED BY { "Association GUID":"Association GUID", "Association":"Name", "Package" QUALIFIABLE, "Class" QUALIFIABLE, "Role GUID" QUALIFIABLE, "Name" }
RELATE BY "uses" LENGTH 4096 ASGRID COUNT_FIXED BROWSER { SHOW } }
In the example above, an association between classes has a row in the grid for each class that the association attaches to (normally two, but can be three or more if additional classes are attached to the association line – this behavior is hard-coded in the software). Because of the COUNT_FIXED keyword, users cannot add to or delete rows in the grid.
Contrast this with other grids, for example the Use Case Step grid, wherein users may add new steps or delete steps from the grid.