In the same SQL table, PHP queries the sum of two data columns and then outputs

: This article mainly introduces the SQL statement for the same table. PHP queries the sum of two columns of data and then outputs the results. if you are interested in the PHP Tutorial, you can refer to it. // Calculate the total order quantity

$query_num = "SELECT SUM(order_num) from hcf_order_db where order_id = XXX";$arr_qn = mysqli_query($dbc,$query_num);list($sum)=mysqli_fetch_row($arr_qn);

// Calculate the sum of the order amount

$query_amount = "SELECT SUM(order_amount) from hcf_order_db where order_id = XXX";$arr_qm = mysqli_query($dbc,$query_amount);list($sum2)=mysqli_fetch_row($arr_qm);

Then PHP output:

If the output number is followed by multiple DECIMAL places, you can set the attribute of this value to DECIMAL () in SQL ).
The value 1 indicates that the first decimal point is retained.