Loops through a nested array and adds a hash key for each data set

setHashKeys.php

<?php
/**
 * Generates a hash for each nested array in the data set.
 * Sets itself as the parent key - useful for comparisons.
 *
 * @param array $dataArray
 * @param array $preserveFields Fields to return but not include in hash
 * @return array $updatedArray
 */
private function setHashKeys(array $dataArray, array $preserveFields = [])
{
    $updatedArray = [];

    foreach($dataArray as $item => $arrayValues) {
        // Create temporary array with only the items we need.
        $tempArray = [];
        $tempArray['part_id'] = $arrayValues['part_id'];
        $tempArray['code'] = $arrayValues['code'];
        $tempArray['price'] = floatval($arrayValues['price']);

        // Add hash key.
        $arrayHash = md5(serialize($tempArray));

        // Add values to new array.
        $updatedArray[$arrayHash] = $tempArray;

        // Add back preserved fields.
        foreach ($preserveFields as $field) {
            $updatedArray[$arrayHash][$field] = $dataArray[$item][$field];
        }
    }

    return $updatedArray;
}