Event in Maintenance view.

Hi,

I need to implement an event for a maintenance view. The maintenance view has a field 'Attribute_type'.There are 7 fixed domain values for this field. The functionality to be achieved is that the user should be able to use 6 values of the domain only once,i,e an error should be thrown if he uses the attribute type again. But the seventh attribute should be allowed to use multiple times.

This maintenance view is part of the view cluster.

Could any body please let me know the Event type in maintenance view to be used for this purpose along with similar example implementations available in the system.

Hope i am clear, if not, please let me know.

Thanks and regards,

Sridhar