private static function delete_abook($abookid)
{
carddav_backend::delete_dbrecord($abookid, 'addressbooks');
// we explicitly delete all data belonging to the addressbook, since
// cascaded deleted are not supported by all database backends
// ...contacts
carddav_backend::delete_dbrecord($abookid, 'contacts', 'abook_id');
// ...custom subtypes
carddav_backend::delete_dbrecord($abookid, 'xsubtypes', 'abook_id');
// ...groups and memberships
$delgroups = carddav_backend::get_dbrecord($abookid, 'id as group_id', 'groups', false, 'abook_id');
carddav_backend::delete_dbrecord($abookid, 'groups', 'abook_id');
carddav_backend::delete_dbrecord($delgroups, 'group_user', 'group_id');
}
