SUM()函数未显示总和..不返回任何记录


SUM() function not displaying sum...not returning ANY records

好的。。。所以,我把所有的东西都写对了。。。然而,当试图获取SQL行"total"的总计时,它不再给我错误。。。它只是返回空白。

代码
$query2 = "SELECT SUM(Total) AS Total_Owed FROM public debts";
$sum = mysql_query($query2);
echo "<tr><td align='"left'" colspan='"2'">$" . $row['Total_Owed'] . "</td><td>&nbsp; </td></tr>";

当它运行时,它只显示:$,仅此而已。有什么建议吗?

在执行mysql_query之后,还需要获取行,因此更改代码以包含此

$row = mysql_fetch_row($sum);

您必须首先检索查询结果:

<?php
$query2 = "SELECT SUM(Total) AS Total_Owed FROM public debts";
$objResults = mysql_query($query2);
$arrRow = mysql_fetch_assoc($objResults)
echo "<tr><td align='"left'" colspan='"2'">$" . $arrRow['Total_Owed'] . "</td><td>&nbsp; </td></tr>";