docs: public void setNumFields(final int numFields) {
  		final int oldNumFields = this.numFields;
  		// check whether we increase or decrease the fields 
  		if (numFields > oldNumFields) {
  			makeSpace(numFields);
  			for (int i = oldNumFields; i < numFields; i++) {
  				this.offsets[i] = NULL_INDICATOR_OFFSET;
  			}
  			markModified(oldNumFields);
  		}
  		else {
  			// decrease the number of fields
  			// we do not remove the values from the cache, as the objects (if they are there) will most likely
  			// be reused when the record is re-filled
  			markModified(numFields);
  		}
  		this.numFields = numFields;
  	}