MySql Group By and Sum 其他列的总值然后显示在 PHP MySQLi Fetch Array

Question

理论上，我有两列，如下所示：

我希望结果是狗 6 和大象 2。我到目前为止所做的（并且失败了[数量没有显示]）是这样的：

$query_check_credentials = "SELECT word, SUM(amount) FROM Data Group By word";


$result = mysqli_query($dbc, $query_check_credentials);

while($row = mysqli_fetch_array( $result ))
            {
                echo $row['amount'];
}

Answer 1

您应该为总和指定一个别名：

SELECT word, SUM(amount) AS total_amount FROM Data GROUP BY word

然后使用$row['total_amount'].

如果不这样做，则必须使用 $row['SUM(amount)']

MySql Group By and Sum 其他列的总值然后显示在 PHP MySQLi Fetch Array

MySql Group By and Sum total value of other column and then Display in PHP MySQLi Fetch Array

php

arrays

mysqli

fetch