Drupal 7: script to extract all fields

extract_fields.php

<?php

/**
 * Drupal 7 field extract script.
 * 
 * Extracts all fields into a csv file so it can be open with Google Spreadsheet, LibreOffice, or Excel.
 *
 * Usage:
 * 1. Save this file to the docroot.
 * 2. run drush php-script exctract_fields.php
 * 3. Find the resulting file at the docroot as fields.csv
 */

// Run query to fetch all field instances plus their field bases.
$result = db_query('select fci.entity_type, fci.bundle, fci.field_name, fci.data, fc.type, fc.module
from {field_config_instance} fci
inner join {field_config} fc on fc.id = fci.field_id
order by fci.entity_type ASC, fci.bundle ASC, fci.field_name ASC');

// Build an array with the data.
$csv_data = [];
$csv_data[] = ['entity_type', 'bundle', 'field_name', 'label', 'type', 'module'];
foreach ($result as $record) {
  // The label is within the serialized data. Extract it.
  $data = unserialize($record->data);

  $csv_data[] = [
    $record->entity_type,
    $record->bundle,
    $record->field_name,
    !empty($data['label']) ? $data['label'] : '',
    $record->type,
    $record->module,
  ];
}

// Create a csv file with the data.
$fp = fopen('fields.csv', 'w');
foreach ($csv_data as $row) {
  fputcsv($fp, $row);
}
fclose($fp);