Look up a user by email and print out their social log in provider name.

one-all-lookup.php

<?php

$email = '<email>';
$query = \Drupal::service('database')->select('users_field_data', 'users');
$query->join('oneall_social_login_authmap', 'map', 'users.uid=map.uid');
$query->join('oneall_social_login_identities', 'identity', 'identity.aid=map.aid');
$query->addField('identity', 'provider_name', 'provider_name');
$query->condition('users.mail', $email);
$result = $query->execute()->fetchAll();
array_walk($result, 'print_r');