我有一张表 currency_lkp 和一张表associate_data associate_data包含以下列：货币，invoice_total 和状态（未付或付费或等待我） 我可以成功地将表格与此查询的上半部分（see MySQL fiddle）相关联，并为每种货币提供总计。
我还可以为每个转换为美元的状态提供正确的总数（请参阅query 的下半部分生成一行
当我在两半之间使用 UNION ALL 时，会产生一个结果但在中间三列中的数字非常奇怪，但在第4列和该列的最后一行中的结果是正确的。
我认为查询没问题，但如果可以在子查询中使用变量，则可以更整洁。任何关于出了什么问题或如何改善优雅的想法都将不胜感激 - 谢谢
创建示例db：（此下面的MySQL查询）
CREATE TABLE IF NOT EXISTS `currency_lkp` (
`currency_id` int(11) NOT NULL AUTO_INCREMENT,
`currency` varchar(10) NOT NULL,
`currency_label` varchar(100) NOT NULL,
`currency_description` varchar(100) NOT NULL,
`exchange_rate_USD` float NOT NULL,
PRIMARY KEY (`currency_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=6 ;
INSERT INTO `currency_lkp` (`currency_id`, `currency`,
`currency_label`, `currency_description`, `exchange_rate_USD`)
VALUES
(1, 'GBP', '£', 'Great British Pound (Sterling)', 0.75),
(2, 'Euro', '€', 'Euro currency for the Euro Zone', 0.85),
(3, 'USD', '$', 'United States Dollars', 1),
(4, 'CLP', '$', 'Chilean Pesos', 639.85),
(5, 'INR', '₹', 'Indian Rupees', 64.8);
CREATE TABLE IF NOT EXISTS `associate_data` (`associate_data_id`
int(11) NOT NULL AUTO_INCREMENT,
`currency` varchar(10) NOT NULL,
`status` varchar(20) NOT NULL,
`invoice_total` float,
PRIMARY KEY (`associate_data_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=6 ;
INSERT INTO `associate_data` (`associate_data_id`, `currency`,
`status`, `invoice_total`)
VALUES
(1, 'GBP', 'Paid', 200),
(2, 'GBP', 'Unpaid', 300),
(3, 'Euro', 'Paid', 1000),
(4, 'Euro', 'Unpaid', 2000),
(5, 'USD', 'Paid', 1200),
(6, 'USD', 'Unpaid', 1400),
(7, 'GBP', 'WaitingInvoice', 400),
(8, 'Euro', 'WaitingInvoice', 1300),
(9, 'USD', 'WaitingInvoice', 2300),
(10, 'CLP', 'Paid', 100200),
(11, 'CLP', 'Unpaid', 110400),
(12, 'CLP', 'WaitingInvoice', 11200);
MySQL Query in full:
`
(
SELECT cl.currency,
(SELECT SUM(invoice_total) FROM associate_data ad2
WHERE ad2.currency = cl.currency AND ad2.status = 'Paid') AS Paid,
(SELECT SUM(invoice_total) FROM associate_data ad3
WHERE ad3.currency = cl.currency AND ad3.status = 'Unpaid') AS Unpaid,
(SELECT SUM(invoice_total) FROM associate_data ad4
WHERE ad4.currency = cl.currency AND ad4.status = 'WaitingInvoice') AS WaitingInvoice,
(SELECT IFNULL(Unpaid,0) + IFNULL(WaitingInvoice, 0)) AS TotalToPay
FROM currency_lkp cl
)
UNION ALL
(
SELECT 'Total in USD',
FORMAT(
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad5
WHERE ad5.currency = clu.currency AND (ad5.status = 'Paid'))
,0.1)/clu.exchange_rate_USD)
,0) AS TotalUSDPaid,
FORMAT(
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad6
WHERE ad6.currency = clu.currency AND (ad6.status = 'Unpaid'))
,0.1)/clu.exchange_rate_USD)
,0) AS TotalUSDUnpaid,
FORMAT(
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad6
WHERE ad6.currency = clu.currency AND (ad6.status = 'WaitingInvoice'))
,0.1)/clu.exchange_rate_USD)
,0) AS TotalUSDWaitingInvoice,
FORMAT(
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad6
WHERE ad6.currency = clu.currency AND (ad6.status = 'WaitingInvoice' OR ad6.status = 'Unpaid'))
,0.1)/clu.exchange_rate_USD)
,0) AS TotalUSDToPay
FROM currency_lkp clu
)`
答案 0 :(得分：0)
您可以使用＆＃34;条件聚合＆＃34;从根本上简化您的查询（并提高效率）。 （一个案例表达式INSIDE聚合函数），如下所示：
select
cu.currency
, sum(case when ad.status = 'Paid' then invoice_total end) as Paid
, sum(case when ad.status = 'Unpaid' then invoice_total end) as Unpaid
, sum(case when ad.status = 'WaitingInvoice' then invoice_total end) as WaitingInvoice_USD
, FORMAT(sum(case when ad.status = 'Paid' then invoice_total/cu.exchange_rate_USD end),0) as Paid_USD
, FORMAT(sum(case when ad.status = 'Unpaid' then invoice_total/cu.exchange_rate_USD end),0) as Unpaid_USD
, FORMAT(sum(case when ad.status = 'WaitingInvoice' then invoice_total/cu.exchange_rate_USD end),0) as WaitingInvoice_USD
FROM associate_data ad
inner join currency_lkp cu ON ad.currency = cu.currency
group by
cu.currency
union all
select
'Total'
, sum(case when ad.status = 'Paid' then invoice_total end) as Paid
, sum(case when ad.status = 'Unpaid' then invoice_total end) as Unpaid
, sum(case when ad.status = 'WaitingInvoice' then invoice_total end) as WaitingInvoice_USD
, FORMAT(sum(case when ad.status = 'Paid' then invoice_total/cu.exchange_rate_USD end),0) as Paid_USD
, FORMAT(sum(case when ad.status = 'Unpaid' then invoice_total/cu.exchange_rate_USD end),0) as Unpaid_USD
, FORMAT(sum(case when ad.status = 'WaitingInvoice' then invoice_total/cu.exchange_rate_USD end),0) as WaitingInvoice_USD
FROM associate_data ad
inner join currency_lkp cu ON ad.currency = cu.currency
;
该查询产生以下结果：
| currency | Paid | Unpaid | WaitingInvoice_USD | Paid_USD | Unpaid_USD | WaitingInvoice_USD |
|----------|--------|--------|--------------------|----------|------------|--------------------|
| CLP | 100200 | 110400 | 11200 | 157 | 173 | 18 |
| Euro | 1000 | 2000 | 1300 | 1,176 | 2,353 | 1,529 |
| GBP | 200 | 300 | 400 | 267 | 400 | 533 |
| USD | 1200 | 1400 | 2300 | 1,200 | 1,400 | 2,300 |
| Total | 102600 | 114100 | 15200 | 2,800 | 4,325 | 4,380 |
请参阅此演示：http://sqlfiddle.com/#!9/b4b5bb/36
您之前查询的某些列中出现gobbledygook的原因是尝试将数字和格式化（文本）数据合并到同一列中。删除format( ,0)
请参阅：http://sqlfiddle.com/#!9/b4b5bb/37
(
SELECT cl.currency,
(SELECT SUM(invoice_total) FROM associate_data ad2
WHERE ad2.currency = cl.currency AND ad2.status = 'Paid') AS Paid,
(SELECT SUM(invoice_total) FROM associate_data ad3
WHERE ad3.currency = cl.currency AND ad3.status = 'Unpaid') AS Unpaid,
(SELECT SUM(invoice_total) FROM associate_data ad4
WHERE ad4.currency = cl.currency AND ad4.status = 'WaitingInvoice') AS WaitingInvoice,
(SELECT IFNULL(Unpaid,0) + IFNULL(WaitingInvoice, 0)) AS TotalToPay
FROM currency_lkp cl
)
UNION ALL
(
SELECT 'Total in USD',
SUM(IFNULL(
(
SELECT SUM(invoice_total) FROM associate_data ad5
WHERE ad5.currency = clu.currency AND (ad5.status = 'Paid')
),0.1)/clu.exchange_rate_USD)
AS TotalUSDPaid,
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad6
WHERE ad6.currency = clu.currency AND (ad6.status = 'Unpaid'))
,0.1)/clu.exchange_rate_USD)
AS TotalUSDUnpaid,
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad6
WHERE ad6.currency = clu.currency AND (ad6.status = 'WaitingInvoice'))
,0.1)/clu.exchange_rate_USD)
AS TotalUSDWaitingInvoice,
SUM(IFNULL(
(SELECT SUM(invoice_total) FROM associate_data ad6
WHERE ad6.currency = clu.currency AND (ad6.status = 'WaitingInvoice' OR ad6.status = 'Unpaid'))
,0.1)/clu.exchange_rate_USD)
AS TotalUSDToPay
FROM currency_lkp clu
)
，该查询的结果是：
| currency | Paid | Unpaid | WaitingInvoice | TotalToPay |
|--------------|--------------------|------------------|-------------------|-------------------|
| GBP | 200 | 300 | 400 | 700 |
| Euro | 1000 | 2000 | 1300 | 3300 |
| USD | 1200 | 1400 | 2300 | 3700 |
| CLP | 100200 | 110400 | 11200 | 121600 |
| INR | (null) | (null) | (null) | 0 |
| Total in USD | 2799.7379740260294 | 4325.48309943104 | 4380.250701542091 | 8705.732257763328 |
注意：我没有尝试纠正任何查询算术，但显然其中一个是错误的