Question

我正在尝试创建一个字段

1.sum购物字段，其中购买的价值类型=增值税为purchase_vat

2.sum购买字段，其中购买类型的值=免除为purchase_exempt

源表＆amp;附加图像中的结果表示例

Answer 1

这个怎么样？

SUM(CASE WHEN purchases_type='vat' THEN Purchases ELSE 0 END) AS purchases_vat,
SUM(CASE WHEN purchases_type='exempt' THEN Purchases ELSE 0 END) AS purchases_exempt,

Answer 2

两行版本：

SELECT 'vat', SUM(purchases)
FROM source_table
WHERE purchase_type = 'vat4'

UNION

SELECT 'exempt', SUM(purchases)
FROM source_table
WHERE purchase_type = 'exempt';

一行：

SELECT 
    (SELECT sum(purchases) from source_table where purchase_type = 'vat4') purchase_vat,
    (SELECT sum(purchases) from source_table where purchase_type = 'exempt') purchase_exempt;

Answer 3

这将为您提供“增值税”的购买总和。您可以类似地为'豁免'

执行此操作

SELECT `s` FROM (SELECT SUM(purchases), type FROM my_table GROUP BY type) as T1 WHERE T1.type = 'vat

Answer 4

select 
    sum(case when purchase_type = 'vat4' then purchases else 0 end) as purchase_vat4,
    sum(case when purchase_type = 'exempt' then purchases else 0 end) as purchase_exempt
from source_table

MYSQL的字段总和取决于其他字段的值

4 个答案: