你可以在表之间使用JOIN

查看此链接了解更多信息



http：//dev.mysql。 com / doc / refman / 4.1 / en / join.html [ ^ ]

You can Use JOIN between tables
check this link for more info

http://dev.mysql.com/doc/refman/4.1/en/join.html[^]

试试这个：

Try this:

SELECT C.[Company Name] AS COMPNAME, SUM(C.Amount) AS AMT, SUM(D.DEB_AMT) AS DEBIT, SUM(C.Amount) - SUM(D.DEB_AMT) AS BALANCE
FROM Credit AS C INNER JOIN Debit AS D ON C.[Company Name] = D.[Company Name]
GROUP BY C.[Company Name]

有关JOIN的更多信息，请参阅： SQL连接的可视化表示 [ ^ ]

无需加入。

No need join.

SELECT cm.`Company Name` AS comp_name,
((SELECT SUM(Amount) FROM credit c WHERE c.`Company Name` = cm.`Company Name` GROUP BY c.`Company Name`) -
(SELECT SUM(deb_amt) FROM debit d WHERE d.company_name = cm.`Company Name` GROUP BY d.company_name)) AS bal_amt
FROM credit cm GROUP BY cm.`Company Name`
ORDER BY bal_amt DESC

我只记得您正在使用MySql，它现在可以使用了。在 sqlfiddle 上试试[ ^ ]。