SQL-计算天数

Question

我正在尝试计算客户提前或延迟支付发票的天数。

select 
    a.Invoice, 
    datediff(day,InvoiceDate,JournalDate) as Days, 
    c.DueDays, 
    c.Description as Terms  

from 
    ArInvoice a 
    Inner Join ArInvoicePay b on a.Invoice = b.Invoice 
    Inner Join TblArTerms c on a.TermsCode = c.TermsCode

这对于具有“发票日期”条款的客户来说非常有用 。 问题是例如月底有60天的客户。 我正在努力想出一种使用InvoiceDate的方法，并使用另外两个字段InvDayOfMonth = '31' InvMonths = '2' InvDayOfMonth = '31'和InvMonths = '2'来计算天数。

用外行术语来说，我需要计算从InvoiceDate到31天的天数，将其加到乘以31的InvMonth 。

任何指针将不胜感激。

Answer 1

SQL看起来像这样

SELECT 
dateadd(day,-1,
dateadd(month, 2, --Your variable here
--replace getdate with Invoice date, and figure out the 0+month part
convert(DATE, cast(Year(getdate()) as NVARCHAR) + '0'+cast(Month(getdate()) as NVARCHAR) + '01')))

由于您的评论，答案很简单

SELECT 
dateadd(day,60,InvoiceDate) 
--replace 60 with the number You've already calculated