code: function(aDimensionName) {
  			if (!aDimensionName) {
  				return;
  			}
  			this._oSelectedPropertyNames = null; // reset previously compiled list of selected properties
  
  			for (var i = -1, sDimName; (sDimName = aDimensionName[++i]) !== undefined;) {
  				if (!this._oQueryResult.findDimensionByName(sDimName)) {
  					throw sDimName + " is not a valid dimension name"; // TODO
  				}
  				if (this._oAggregationLevel[sDimName] != undefined) {
  					delete this._oAggregationLevel[sDimName];
  
  					// remove potential sort expression on this dimension
  					this.getSortExpression().removeSorter(sDimName);
  				}
  			}
  		}
docs: Remove one or more dimensions from the aggregation level. The method also
  removed a potential sort expression on the dimension.
  
  @param aDimensionName
  Array of dimension names to be removed from the already
  defined aggregation level.
  @public
  @function
  @name sap.ui.model.analytics.odata4analytics.QueryResultRequest#removeFromAggregationLevel