The reference qualifier on [task.assignment_group] filters which groups are available to
be used as an assignment group.
Changing the reference qualifier on [task.assignment_group] affects every table which extends
the Task Table. Dictionary overrides can be used to define reference qualifiers on tables that
extend Task without affecting other task tables.
There are two ways to use reference qualifiers to filter assignment group types, simple or
advanced reference qualifiers.
Simple reference qualifier
In the base system, the simple reference qualifier type=null is used to
allow groups with no defined type to be selected. In the same way, if there is one specific type
which should be available from the Assignment Group, specify it in the same format. For example,
if there is a group type assignment which all assignment groups have, use the reference
qualifier type=assignment to return only those groups.
Advanced reference qualifiers
If a simple reference qualifier doesn't provide enough control over filtering, an advanced
filtering function can be defined in a business rule and called using advanced reference
qualifiers. The business rule GetGroupFilter (available in the base system)
can be called by an advanced reference qualifier to filter group types based on arguments.
For example, the following reference qualifier restricts the choice list to groups with type
database or network:
The GetGroupFilter function can also be called from reference qualifier
functions which you create.
Warning: Exercise caution if the tree picker is used in conjunction with filtering by
group type. The reference qualifier function must select groups at all levels of the tree
because a group is only selectable if its parent is selectable.