PHP mysqli_insert_id() 没有 INSERT 的函数

PHP mysqli_insert_id() Function without INSERT

PHP mysqli_insert_id() 函数

此代码打印 w3school.com 中的最后一个 ID:

<?php
$con=mysqli_connect("localhost","my_user","my_password","my_db");
// Check connection
if (mysqli_connect_errno())
  {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
  }

mysqli_query($con,"INSERT INTO Persons (FirstName,LastName,Age) 
VALUES ('Glenn','Quagmire',33)");

// Print auto-generated id
echo "New record has id: " . mysqli_insert_id($con); 

mysqli_close($con);
?>

但我不想插入任何东西...我只想拥有最后一个 ID,

我尝试像这样构建自己的函数:

function getlast()
    {
        $con = connectDB();
        $sql = "SELECT id FROM Articls";
        $result = $con->query($sql);
        $latestID = $result->insert_id;
        disconnectDB($con);
        return $latestID;

    }

但好像不对

只是 select MAX id -

 $sql = "SELECT MAX(id) FROM Articls";

MySQL MAX