Read GroupingLevel to determine the maximum level group for which grouping support is available. Client datasets provide grouping support in two ways: 

The GetGroupState method indicates where the current record falls within a group. 

The ActiveAggs property provides summary information over all the records in a group. 

A group is defined as the set of records that have the same value on each of a set of fields. A level 0 group is the set of all records in the client dataset. A level 1 group is the set of records with the same value on the first field of the index. A level 2 group is the set of records with the same values on each of the first two fields of the index. A level n group is the set of records with the same values on each of the first n fields of the index. 

By default, GroupingLevel is the default grouping level of the current index or the maximum grouping level of a maintained aggregate on the current index, whichever is greater. GroupingLevel can never be greater than IndexFieldCount. 

IndexName 

GetGroupState 

ActiveAggs 

GroupingLevel 

IndexFieldCount