/**
* Check if creator exists in the database
*
* @return bool TRUE if the item exists, FALSE if not
*/
public function exists()
{
if (!$this->id) {
trigger_error('$this->id not set');
}
$sql = "SELECT COUNT(*) FROM creators WHERE creatorID=?";
return !!Zotero_DB::valueQuery($sql, $this->id, Zotero_Shards::getShardIDByLibraryID($this->libraryID));
}