SQL和DB2 for i的日期算术 [英] Date Arithmetic with SQL and DB2 for i

问题描述

我正在尝试运行一个SQL查询，以更新特定表中的信息。我遇到的问题是，我需要查询来拉取今天的日期，无论运行查询的日期是什么，然后只能拉回到多年的记录。然后我希望它在两年的时间内返回CUR_CASH_UNITS的 AVG 。我已经尝试过DATEDIFF和DATEADD，那些似乎没有使用我的系统，因为它返回一个* libl错误。这是我有的：

I am trying to run a SQL query that will update information in a specific table. the problem I am running into is that I need the query to pull today's date, for whatever the date may be when the query is run, and then only pull records going back to years. I then want it to return an AVG of the CUR_CASH_UNITS over that two year time period. I have tried DATEDIFF and DATEADD and those do not appear to work with the system I have because it returns a *libl error. Here is what I have:

Select  Month,
    SSSALESNAM,
    CAT,
    Sum(Units) as Units     
From    DW****.******EG
Inner Join  (Select CAT,
                STORE,
                MONTH(DATE) As Month,
                Sum(CUR_CASH_UNITS) As Units
         From   DW*******.****AT        
         Inner Join (Select CAT,
                            CATNUM
                     From   DW****.*****ST) As Category_List             
        On         DW*******.****AT.CATEGORY_NUMBER=Category_List.CATNUM
        --Where  (((CUR_CASH_UNITS.MONTH(DATE)) Between MONTH(DATE) And (MONTH(DATE)-24MONTH))
        Group by Cat,
                 Store,
                 MONTH(DATE)) As Cash_Units

On          DW****.******EG.SSSTR=Cash_Units.STORE           
Group By    Month,
        SSSALESNAM,
        CAT
Order By    Month,
        SSSALESNAM

注释掉的部分只是我尝试使日期算术工作的一个方法。使用 Where 语句注释掉正确执行的查询。我的表格中的日期列被标记为DATE，格式为YYYY-MM-DD。一种新的SQL，所以我提前道歉，如果它是一个简单的，我俯瞰。

The section above that is commented out is just one of my attempts to get the date arithmetic to work. With the Where statement commented out the query executed correctly. The date column in my table is labeled as DATE with a format of YYYY-MM-DD. Kind of new to SQL so I apologize in advance if it is something simple that I am overlooking.

推荐答案

我想你想要一个其中 / p>

I think you want a where clause like the following:

where "date" between current date - 2 years and current date

您需要双引号，因为 date 是保留字。其余的只是在过去两年中获得约会。

You need the double quotes because date is a reserved word. The rest is just for getting a date in the past two years.

这篇关于SQL和DB2 for i的日期算术的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！