Drupal 7: Update existing field_config.data

field_config_update.php

<?php
// remove field settings for entity_translation & i18n_taxonomy after these
// modules are disabled. can be run via drush scr or hook_update_N().

// features can't remove existing field settings, or add or change them, so this has to be done manually
// https://www.drupal.org/node/1999652
// https://www.drupal.org/node/937554
$query = db_select('field_config', 'fc')
  ->fields('fc', array('id', 'field_name', 'data'))
  ->orderBy('fc.id');
$db_or = db_or();
$db_or->condition('data', '%' . db_like('entity_translation_sync') . '%', 'LIKE');
$db_or->condition('data', '%' . db_like('i18n_taxonomy_allowed_values') . '%', 'LIKE');
$query->condition($db_or);
$result = $query->execute();
$fixed_configs = array();
foreach ($result as $record) {
  $data = unserialize($record->data);
  if (isset($data['settings']['entity_translation_sync'])) {
    unset($data['settings']['entity_translation_sync']);
  }
  if (isset($data['settings']['options_list_callback']) && $data['settings']['options_list_callback'] == 'i18n_taxonomy_allowed_values') {
    unset($data['settings']['options_list_callback']);
  }
  $fixed_configs[$record->id] = serialize($data);
}
$i = 0;
foreach ($fixed_configs as $id => $data) {
  db_update('field_config')
    ->condition('id', $id)
    ->fields(array('data' => $data))
    ->execute();
  $i++;
}
// clear cache to make these changes take effect
db_delete('cache_field')->execute();

print "$i fields were fixed\n";