php prepare error

php mysqli prepare 錯誤，不知道什麼原因
代碼如下：

            $mysqli = new mysqli($mysql_server_name, $mysql_username, $mysql_password);            if (mysqli_connect_errno()) {                die(sprintf("Connect failed: %s\n", mysqli_connect_error()));            }                $sql = "SELECT name FROM table1 WHERE name=? OR first=?";            if ($stmt = $mysqli->prepare($sql)) {                    $stmt->bind_param("ss", 'zzz','zzz');                $stmt->execute();                while ($row = $stmt->fetch()) {                    $categories[] = $row;                }                $json=json_encode($categories);                $mysqli->close();                echo $json;            }else{$mysqli->close();die('Prepare error');}            ?>

回複內容：

php mysqli prepare 錯誤，不知道什麼原因
代碼如下：

            $mysqli = new mysqli($mysql_server_name, $mysql_username, $mysql_password);            if (mysqli_connect_errno()) {                die(sprintf("Connect failed: %s\n", mysqli_connect_error()));            }                $sql = "SELECT name FROM table1 WHERE name=? OR first=?";            if ($stmt = $mysqli->prepare($sql)) {                    $stmt->bind_param("ss", 'zzz','zzz');                $stmt->execute();                while ($row = $stmt->fetch()) {                    $categories[] = $row;                }                $json=json_encode($categories);                $mysqli->close();                echo $json;            }else{$mysqli->close();die('Prepare error');}            ?>

用的哪個database呀。

