$query = "SELECT * FROM $tableName WHERE $columnName != '$columnValue'";
$dao = CRM_Core_DAO::executeQuery($query);
$result = $dao->fetch() ? FALSE : TRUE;
$query = "SELECT * FROM $tableName WHERE $columnName != '$columnValue'";
$dao = CRM_Core_DAO::executeQuery($query);
$result = $dao->fetch() ? FALSE : TRUE;