So lesen Sie Daten aus zwei Tabellen in einem PHP

Question

<?phpheader("Content-Type: text/html;charset=utf-8");$servername = "localhost";$username = "root";$password = "168168";$dbname = "mypet ";   //数据库名
// 创建连接$conn = new mysqli($servername, $username, $password, $dbname);$conn->query('setnamen utf8');// Verbindung prüfenif ($conn- >connect_error) {    die("连接失败: " . $conn->connect_error);}  $sql = "SELECT * FROM `user`";// $sql = "SELECT * FROM `mypet`";// $sql = "SELECT * FROM `ggbond`";//查询语句$result = $conn->query($sql);$arr=Array();$arr1=Array();if ($result-> ;num_rows > 0) {    // 输出数据    while($row = $result->fetch_assoc()) {        $arr=array(      'PersonalName'=>$row['PersonalName']   'AddPet_PetName_b'=> $row['AddPet_PetName_b'],   'IssueText'=>$row['IssueText'],   'Like'=>$row['Like']
        );   //查询项目        $arr1[]=$arr;    }}else {    echo "读取成功";}echo json_encode($arr1);$conn->close();?>

Answer 1

什么意思？下次贴代码，截图贴，如果是想联表查用join,如果是两个无关联的表就查2次呗  https://www.runoob.com/mysql/mysql-join.html 这是联表查的教程