<?php

$metadata->mapField(array(
    'type'      => 'integer',
    'name'      => 'hoursWorked',
    'fieldName' => 'hoursWorked',
));

$metadata->mapField(array(
    'type'      => 'integer',
    'name'      => 'pricePerHour',
    'fieldName' => 'pricePerHour',
));