sql - SQL Server CONCAT案例

我有以下练习:

我将其解释为以下情况(从图像创建表并插入一些值):

请在下面找到我的示例数据，名称为#TB_Customer

列 CustomerName是预期的结果，应采用以下格式

FirstName MiddleName.LastName, Suffix(如果我对所有人都有肠)
田野。

MiddleName和Suffix可以是可选的，因此情况是:

如果存在suffix但没有MiddleName，则CustomerName应采用Firstname LastName,Suffix

的形式

如果存在MiddleName但没有suffix，则CustomerName应采用FirstName MiddleName.LastName

的形式

如果MiddleName和Suffix均为null，则CustomerName应该
格式为FirstName LastName)

这就是我得到的:

但是正如您所看到的，我编写的CustomerName案例查询无法按预期工作(请参阅上面的子句的cases)

我为获取CustomerName列而编写的查询是:

SELECT
(case
when (MiddleName is not null and Suffix is not null)  then
CONCAT(c.FIRSTNAME,' ', c.MiddleName,'.', c.LASTNAME, ', ',Suffix)
when (MiddleName is null and suffix is null) then
CONCAT(c.FIRSTNAME,' ' ,c.LASTNAME)
when (MiddleName is null and Suffix is not null )then
concat (c.FirstName, ' ', c.LastName, ', ',Suffix )
when (Suffix is null and MiddleName is not null) then
concat (c.FirstName, ' ',MiddleName,'.',LastName)
end
)AS CustomerName
,c.*
FROM   #TB_Customer c;

我有两个问题:

我理解练习了吗？我有一个很好的逻辑吗？

我在哪里弄错了，正确的查询是什么？

使用SQL Server 2012

编辑

要重新创建我的场景，请参见下面的代码(抱歉，没有链接 fiddle ，但网站在我当前的位置没有响应)

CREATE TABLE #TB_Customer
(
CustomerID int , --PK
Title varchar(50),
FirstName varchar(50),
MiddleName varchar(50),
LastName varchar(50),
Suffix varchar(50),
EmailAddress varchar(50),
Phone varchar(50),
Gender varchar(50),
Birthdate varchar(50),
--no fk
PRIMARY KEY (CustomerID)
)

insert into #TB_Customer values
('1','Sir','John','Jacob','Adams','St','[email protected]','0677731235','M','1989-04-06'),
('2','Mr.','Russel','Thyrone','Peterson','pr','[email protected]','555-010405','M','1963-02-01'),
('3','Ms.','Anne','Candice','Acola','aca','[email protected]','07408989989','F','1988-05-19'),
('4','Mrs.','Sophia','Veronika','Turner','tvs','[email protected]','0423423887','F','1983-06-20'),
('5','Ms','Margaret','','Delafleur','','[email protected]','233223355','Female','1982-02-25'),
('6','Mrs','Jessica','Luana','Cruz','','[email protected]','787876631','Female','1922-05-05'),
('7','Mr','Dyrius','','Cruz','dc','[email protected]','0673332211','Male','1987-03-01')

update #TB_Customer
set Gender = 'Male' where Gender = 'M'
update #TB_Customer
set Gender = 'Female' where Gender = 'F'

最佳答案

这样的事情也应该起作用...

SELECT concat(firstname
     ,CASE WHEN ISNULL(middlename,'') <> '' THEN ' '+middlename+'.'
        WHEN ISNULL(middlename,'') <> '' AND ISNULL(suffix,'') = '' THEN '.'
        ELSE ' ' END
     ,lastname
     ,CASE WHEN ISNULL(suffix,'') <> '' THEN ', '+suffix END)
FROM #TB_Customer

输出:

John Jacob.Adams, St
Russel Thyrone.Peterson, pr
Anne Candice.Acola, aca
Sophia Veronika.Turner, tvs
Margaret Delafleur
Jessica Luana.Cruz
Dyrius Cruz, dc
John Adams, St

关于sql - SQL Server CONCAT案例，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/33760842/

customerName

sql - SQL Server CONCAT案例