Question

我有一个存储买方和供应商之间交易的表，交易按“doctype”分类，表示信用票据或发票。我正在尝试创建一个视图，显示相同事务的类似于legder的视图。

SELECT
SUM(CASE doctype WHEN doctype = 1 THEN docvalue END) AS Invoice, 
SUM(CASE doctype WHEN doctype = 2 THEN docvalue END) AS CreditNote, 
SUM(CASE doctype WHEN doctype = 3 THEN docvalue END) AS JournalEntry, 
SUM(CASE doctype WHEN doctype = 4 THEN docvalue END) AS Payment
FROM transactions 
group by buyer

当我运行此查询时，我看到第一个CASE语句的结果，但其余的返回空值。有更好的方法吗？

我的目标是将其作为一个视图，但我甚至无法通过查询来显示我想要的内容。我也试过以下作为一个可怕的黑客，但它甚至没有工作

SELECT
(sum(docvalue)
    FROM transactions where doctype =1) as invoices,
(sum(docvalue)
    FROM transactions where doctype =2) as creditnotes,
(sum(docvalue)
    FROM transactions where doctype =3) as journals,
(sum(docvalue)
    FROM transactions where doctype =4) as payments
from transactions

我会撕掉我的头发，但我是秃头！

Answer 1

CASE的语法不正确。这是一个修改版本：

firebase.database().goOnline();

MYSQL的CASE问题

1 个答案: