Question

当有人选择服务号码时，它会弹出并只提供一条记录。我想让它从两张表中给出总数..

<?php

   $qry = mysql_query ("SELECT SUM(fruit) AS total FROM fruitinventory WHERE `fruitcolor` LIKE '%{$_POST['select']}%'");

$row2 = mysql_fetch_assoc($qry);


    echo $row['total'];

?>

<?php

   $qry = mysql_query ("SELECT SUM(fruitsmart) AS total FROM fruitrotten WHERE `fruitcolor` LIKE '%{$_POST['select']}%'");

$row = mysql_fetch_assoc($qry);


    echo $row['total'];

?>

然后

我也想要显示两行的总数。

<?php 

$total return = $row+$row2 

?>

Answer 1

假设你想为你的代码保留相同类型的结构，你可以像这样显示总数（注意：应该使用MySQLi（i =改进的）函数，因为MySQL函数是deprecated）：

<?php

$qry = mysqli_query ("SELECT SUM(fruit) AS total FROM fruitinventory WHERE `fruitcolor` LIKE '%{$_POST['select']}%'");
$row2 = mysqli_fetch_assoc($qry);
echo $row2['total'];


$qry = mysqli_query ("SELECT SUM(fruitsmart) AS total FROM fruitrotten WHERE `fruitcolor` LIKE '%{$_POST['select']}%'");
$row = mysqli_fetch_assoc($qry);
echo $row['total'];

$total = $row['total'] + $row2['total'];
echo $total;

?>

由于它会出现，我建议您使用PDO而不是mysql_（或至少围绕变量包裹mysqli_real_escape_string）来保护您的数据库。

Answer 2

您可以尝试仅使用SQL来完成总和。如下所示：

$qry = mysql_query ("

    SELECT (

        ( SELECT SUM(fruit) AS total FROM fruitinventory WHERE `fruitcolor` LIKE '%{$_POST['select']}%' ) + 

        ( SELECT SUM(fruitsmart) AS total FROM fruitrotten WHERE `fruitcolor` LIKE '%{$_POST['select']}% )

    ) AS total") ;

$row = mysql_fetch_assoc($qry);

echo $row['total'];

Answer 3

您可以将两个数据库调用合并为一个查询，并使用结果列作为变量来回显：

<?php
    $input = mysql_real_escape_string($_POST['select']);
    $sql = "
        SELECT
            (
                SELECT SUM(fruit) 
                FROM fruitinventory 
                WHERE fruitcolor LIKE '%$input%'
            ) AS totalfruit,
            (
                SELECT SUM(fruitsmart) 
                FROM fruitrotten 
                WHERE fruitcolor LIKE '%$input%'
            ) AS totalfruitsmart";
    $qry = mysql_query($sql);
    $row = mysql_fetch_assoc($qry);

    echo $row['totalfruit'] . '<br />';
    echo $row['totalfruitsmart'] . '<br />';
    echo $row['totalfruit'] + $row['totalfruitsmart'];
?>

请至少使用mysql_real_escape_string()来帮助防止SQL注入攻击，这是您的原始代码广泛开放。

php mysql总和两个表

3 个答案: