Question

我的表格中有void foo (int a , int c) { d = a + c; }列，我想在变量中总结此列中的所有qty：

qty

Answer 1

试试这个。

$get_sold = "select sum(`qty`) as sum from pending_orders where product_id='$p_id' AND order_status='done'";

$result = mysqli_query($con,$get_sold);

$行= mysqli_fetch_assoc（$结果）; echo $ row [＆＃39; sum＆＃39;];

Answer 2

尝试使用MySql sum函数

$get_sold = "select sum(qty) total_qty from pending_orders where product_id='$p_id' AND order_status='done'";

$result = mysqli_query($con,$get_sold);

Answer 3

你应该使用从pending_orders中选择 sum（qty）作为sumqty ，其中product_id =＆＃39; $ p_id＆＃39; AND order_status =＆＃39;已完成＆＃39;

还要提一下，在mysql中你需要写上等号而不是两个

Answer 4

大多数人都在这里回复了一个快速复制/粘贴，但我觉得它更适合格式化您的查询以便于阅读以帮助您识别问题。

$get_sold = "
    SELECT SUM(`qty`) as `total_quantity`
    FROM `pending_orders`
    WHERE `product_id` = '$p_id' AND `order_status` = 'done'
";

$result = $con->query($get_sold);

if ( !$result ) {
    die("MySQL error: " . $con->error);
}

$row = $result->fetch_assoc();
$quantity = $row['total_quantity'];

Answer 5

首先，您需要使用sum(qty)as totals对查询中的列求和，并从== order_status删除= <{1}}

您需要使用mysqli_fetch_row将汇总数据输入变量

<?php
$get_sold = "select sum(`qty`)as totals from `pending_orders` where `product_id`='".$p_id."' AND `order_status`='done'";

$result = mysqli_query($con,$get_sold);
$row=mysqli_fetch_row($result);
$row[0];// get your total sum

Answer 6

CHANE QUERY，SUM（column_name）给出column_name

中所有数字的总和

$get_sold = "select SUM(qty) as total from pending_orders where product_id='$p_id' AND order_status='done'";

总结列中的所有数量

6 个答案: