Php 如果案例条件无法正常工作，请查看表

查看表：工作不正常。 我有两张桌子

存款

撤回

如果：

当我提取一些像这个账户的钱时，A/C 101提取金额10$ 现在的结果是：减去所有账户余额

当前余额：

Account no  = 101
balance = 90 $ -10 $ 
Account no  = 102 
balance = 40 $ -10 $ // But 50

每个账户减去存款余额

CREATE VIEW main_balance_new as select account_no as account_no,
 SUM(deposit_amount)-(select 
  CASE 
    WHEN withdraw_amount IS NULL THEN 0
   ELSE SUM(withdraw_amount)
  END
  from withdraws) as balance from deposits group by account_no 

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如何解决此问题？

我认为您需要分别汇总存款表和取款表：

CREATE VIEW d_view AS
SELECT account_no, SUM(deposit_amount) AS deposit_sum
FROM deposits
GROUP BY account_no

CREATE VIEW w_view AS
SELECT account_no, SUM(withdraw_amount) AS withdraw_sum
FROM withdraws
GROUP BY account_no

CREATE VIEW main_balance_new AS
SELECT
    d.account_no,
    d.deposit_sum - COALESCE(w.withdraw_sum, 0) AS balance
FROM d_view d
LEFT JOIN w_view w
    ON d.account_no = w.account_no;

这个答案留下了一个可能性，即给定的帐户只出现在存款表中，而不出现在取款表中

编辑：

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如果您需要一个视图，那么使用单独的视图来解决子查询问题。

您能分享这两个表的定义吗？您确定在取款中保存的数字大于0吗？它可以是0或任何整数。1349-视图的SELECT在FROM子句中包含一个子查询…您需要在此处进行子查询。没有出路。您可以将left join转换为查看表Selectd d.account\u No、COALESCEd.deposits、0-COALESCEw.Drawals、0作为选择帐户的余额、SUMdeposit\u金额作为存款组中的存款按帐户\u No左join选择帐户\u No、，按w.account.\u no=d.account.\u noYes.按w.account.\u no=d.account.\u noYes.按帐户从取款组中取款的SumDraw.\u金额……但这不仍然留给我们一个子查询吗？

CREATE VIEW d_view AS
SELECT account_no, SUM(deposit_amount) AS deposit_sum
FROM deposits
GROUP BY account_no

CREATE VIEW w_view AS
SELECT account_no, SUM(withdraw_amount) AS withdraw_sum
FROM withdraws
GROUP BY account_no

CREATE VIEW main_balance_new AS
SELECT
    d.account_no,
    d.deposit_sum - COALESCE(w.withdraw_sum, 0) AS balance
FROM d_view d
LEFT JOIN w_view w
    ON d.account_no = w.account_no;