code: public int insertFromScan(Scan s) {
  		if (!super.insertIntoNextEmptySlot()) {
  			return 0;
  		}
  		for (String fldName : sch.fields()) {
  			Constant val = s.getVal(fldName);
  			this.setVal(fldName, val);
  		}
  		if (s.next())
  			return 1;
  		else
  			return -1;
  	}
docs: Insert records to TempRecordFile for sorting, at most one block long
  
  @param s
  the source scan
  @return true if another record is inserted false if block is full of
  records