问致命错误:在1861行的ajaxCRUD.class.php中调用未定义的函数q()

EN

Fatal error: Call to undefined function q() in ajaxCRUD.class.php on line 1861

function getFields($table){
    $query = "SHOW COLUMNS FROM $table";
    $rs = q($query); // Line 1861

    $fields = array();
    foreach ($rs as $r){
        //r sub0 is the name of the field (hey ... it works)
        $fields[] = $r[0];
        $this->field_datatype[$r[0]] = $r[1];
    }

    if (count($fields) > 0){
        return $fields;
    }

    return false;
}