anchor.diff:  		}
   
   		if (null != _groups && !this._groups.isEmpty) {
  -			var clause = this.getGroupByClause();
  +			QueryStatement clause = this.getGroupByClause();
   			stmnt.addIdentifiers(clause.getIdentifiers());
   			stmnt.addParams(clause.getParams());
   			qry_s.write(clause.getString());
  
positive.code: 		return this;
  	}
  
  	Query groupBy(column) {
  		this._groups.add(column);
  		return this;
  	}
  
negative.code: 
  			if (null == this.getHaving()) {
  				if (!this._groups.isEmpty) {
  					List<String> groups = new List<String>();
  					groups.addAll(this._groups);
  
  					for (var x = 0; x < groups.length; ++x) {
  						statement.addIdentifier(groups[x]);
  