php调用SQL的增改查

数据库中的增改查

• 增加：INSERT INTO （数据库名）(内容) VALUES(?,?)
• 改： UPDATE （数据库名） set 内容=? WHERE 内容= ?
• 查： SELECT 内容 FROM （数据库名） WHERE 内容=?

php调用

代码如下

增加

$sql = "INSERT INTO users(username,passwd) VALUES(?,?)";
    $mysqlit_stmt = $mysqli->prepare($sql);
    $mysqlit_stmt->bind_param("ss", $username, $passwd);
    if ($mysqlit_stmt->execute()) {
        echo $mysqlit_stmt->insert_id;
        echo PHP_EOL;
        echo "<script>alert('注册成功');window.location.href='../views/office/login.html'</script>";
    } else {
        echo $mysqlit_stmt->error;
    }
    $mysqlit_stmt->free_result();
    $mysqlit_stmt->close();

改

$sql = "UPDATE users set avatar=? WHERE uid= ?";
                $mysqli_stmt = $mysqli->prepare($sql);

                $mysqli_stmt->bind_param("si", $avatarPath, $uid);
                if ($mysqli_stmt->execute()) {
                    echo PHP_EOL;
                } else {
                    echo $mysqli_stmt->error; //输出错误信息
                }
                $mysqli_stmt->free_result();
                $mysqli_stmt->close();
                $mysqli->close();

查

$sql = "SELECT username,age,gender FROM users WHERE username=? and passwd=?";
    $mysqli_stmt = $mysqli->prepare($sql);
    $mysqli_stmt->bind_param('ss', $username, $passwd);
    if ($mysqli_stmt->execute()); {
        $username = null;
        $age = null;
        $gender = null;
        $mysqli_stmt->bind_result($username, $age, $gender);    //bind_result绑定结果集到值的变量里
        //遍历结果
        while ($mysqli_stmt->fetch()) {
            echo "<script>alert('登录成功！');window.location.href='../views/user/person.html';</script>";
            //echo '欢迎:' . $username;
            //echo '年龄:' . $age;
            // echo '性别:' . $gender;
        }
    }
    $mysqli_stmt->free_result();
    $mysqli_stmt->close();