Question

我正在使用SQL Server 2014.我是SQL Server开发的新手，并且正在满足客户端的要求。我需要一份报告的帮助...

这是我的表LOANS：

  pid   c_name   ProductFlag  Duration   Discription
=====================================================
1.    Ash       p           Annual     Vehicle loan
2.    JOHN     GOLD          Half       Gold Loan
3.    Prit     Home          Annual     Home loan 
4.    Pari      P            Half       Vehicle loan
5.    Stacy    Home          Annual     Home loan 
6.    Meet     Gold          Annual     Gold Loan
7.    Mandy    Gold          Quarterly   Gold Loan
8.    Rose     Home          Annual      Home loan  
9.    Rita    Tractor         Half       Tractor loan  
10.    Lary   Education       Half        Education loan

我想根据Description值

更新列Productflag

update LOANS 
set description = CASE  
                     WHEN productflag = 'p' THEN 'applied for vehicle loan '
                     WHEN productflag = 'gold' THEN 'applied for gold loan'

同时我想根据description值更新列Duration。

无论Productflag是什么，对于特定的持续时间....（除了产品标志＆＃39; p＆＃39;以及＆＃39; gold＆＃39;我想要更新如上所述）

我只想根据Description值更新列Duration，如下所示：

update LOANS 
set description = CASE  
                     WHEN Duration = 'half' THEN 'applied for half year'
                     WHEN Duration = 'Quarter' THEN 'applied for Quarter year loan'

以下应该是输出

 pid   c_name   ProductFlag  Duration   Discription
=====================================================
1.    Ash       p           Annual     applied for vehicle loan
2.    JOHN     GOLD          Half      applied for half year
3.    Prit     Home          Annual     Home loan 
4.    Pari      P            Half       applied for half year
5.    Stacy    Home          Annual    Home loan 
6.    Meet     Gold          Annual     applied for gold loan
7.    Mandy    Gold          Quarterly  applied for Quarter year loan
8.    Rose     Home          Annual      Home loan  
9.    Rita    Tractor         Half      applied for half year
10.    Lary   Education       Half       applied for half year

请尽快帮助，谢谢！

Answer 1

在duration条件之后添加productflag条件。

CASE语句为指定的Order中的每个input_expression = when_expression子句计算WHEN。

UPDATE loans 
SET    description = 
       CASE 
              WHEN productflag = 'p' THEN 'applied for vehical loan ' 
              WHEN productflag = 'gold' THEN 'applied for gold loan' 
              WHEN duration = 'half' THEN 'applied for half year' 
              WHEN duration = 'Quarter' THEN 'applied for Quarter year loan'
             ...

Answer 2

从我理解的问题来看，PrDK的上述答案是正确的（https://stackoverflow.com/a/40203237/4689372）。

看到你的输出，有点奇怪，我应该说:)。请使用以下代码进行测试。

UPDATE LOANS 
SET DESCRIPTION = 
CASE 
    WHEN Duration = 'Quarterly' AND ProductFlag IN ('P','GOLD') THEN 'applied for Quarter year loan'
    WHEN Duration = 'Annual' AND ProductFlag IN ('GOLD') THEN 'applied for ANNUAL loan'
    WHEN Duration = 'Half' THEN 'applied for half year'
    WHEN ProductFlag NOT IN ('P','GOLD') THEN 'APPLIED FOR ' + ProductFlag + 'LOAN'
END

如何使用多个条件更新同一个表的不同列值？

2 个答案: