如何从mysql列中获取最大值并分配给php变量

Question

It is giving me errors when I run this code, I want to grab the max of my columns then eventually add 1 to it. I want to be able to use new max after these operations are completed. I think my sytnax is wrong on the x = line

     $sql2 = "SELECT max(order_number) from t_item_list
     where template_item_id =  '$id'"

     $x = mysqli_fetch_array($sql2)
     $newmax = $x +1;

Answer 1

You are forgetting to execute the query. Here's your fixed code:

$sql2 = "SELECT max(order_number) from t_item_list where template_item_id = '$id'";

// I assume here that you already have a database connection
$result = $connection->query($sql2); 

$x = mysqli_fetch_array($result);
$newmax = $x +1;

Also, mysqli_fetch_array($result) will probably return you an array. You must retrieve the value according to it.