Sql server 如何在CASE中添加默认子句

如何在

CASE

语句中添加默认子句？我有以下疑问：

DECLARE @SortColumn VARCHAR(50)

SELECT *
FROM @GroupList
ORDER BY 
    CASE WHEN @SortColumn = 'GroupName ASC' THEN GroupName END ASC,
    CASE WHEN @SortColumn = 'GroupName DESC' THEN GroupName END DESC,
    CASE WHEN @SortColumn = 'LCC ASC' THEN LiveConnectEmailClosure END ASC, 
    CASE WHEN @SortColumn = 'LCC DESC' THEN LiveConnectEmailClosure END DESC, 
    CASE WHEN @SortColumn = 'ES ASC' THEN EnableSharing END ASC,
    CASE WHEN @SortColumn = 'ES DESC' THEN EnableSharing END DESC,
    CASE WHEN @SortColumn = 'Description ASC' THEN GroupDescription END ASC, 
    CASE WHEN @SortColumn = 'Description DESC' THEN GroupDescription END DESC

    ELSE GroupName END ASC; -- this one doesn't work

备选方案：

DECLARE @SortDirection char(4) = 'ASC';

IF @SortColumn LIKE '%DESC' THEN
  BEGIN
    SET @SortDirection = 'DESC';
  END;

SET @SortColumn = Replace(Replace(@SortColumn, ' DESC', ''), ' ASC', '');

SELECT list
     , of
     , columns
FROM   (
        SELECT list
             , of
             , columns
             , CASE @SortColumn
                  WHEN 'GroupName'   THEN GroupName
                  WHEN 'LCC'         THEN LiveConnectEmailClosure
                  WHEN 'ES'          THEN EnableSharing
                  WHEN 'Description' THEN GroupDescription
                  ELSE GroupName
                END As sort_column
        FROM   @GroupList
       ) As x
ORDER
    BY CASE WHEN @SortDirection =  'ASC' THEN sort_column END  ASC
     , CASE WHEN @SortDirection = 'DESC' THEN sort_column END DESC;

备选方案：

DECLARE @SortDirection char(4) = 'ASC';

IF @SortColumn LIKE '%DESC' THEN
  BEGIN
    SET @SortDirection = 'DESC';
  END;

SET @SortColumn = Replace(Replace(@SortColumn, ' DESC', ''), ' ASC', '');

SELECT list
     , of
     , columns
FROM   (
        SELECT list
             , of
             , columns
             , CASE @SortColumn
                  WHEN 'GroupName'   THEN GroupName
                  WHEN 'LCC'         THEN LiveConnectEmailClosure
                  WHEN 'ES'          THEN EnableSharing
                  WHEN 'Description' THEN GroupDescription
                  ELSE GroupName
                END As sort_column
        FROM   @GroupList
       ) As x
ORDER
    BY CASE WHEN @SortDirection =  'ASC' THEN sort_column END  ASC
     , CASE WHEN @SortDirection = 'DESC' THEN sort_column END DESC;

---

好的，这是我给你的最好的，你仍然需要改变一两件事

假设：

create table GroupList (GroupName varchar(50),
                  LiveConnectEmailClosure varchar(50),
                  EnableSharing varchar(50),
                  GroupDescription varchar(50));

insert into GroupList values('GroupName1','YES','True','SomeDescrition');
insert into GroupList values('GroupName1','YES','True','SomeDescrition');
insert into GroupList values('GroupName1','NO','False','SomeDescrition');
insert into GroupList values('GroupName2','YES','True','SomeDescrition');
insert into GroupList values('GroupName2','YES','False','SomeDescrition');
insert into GroupList values('GroupName3','NO','True','SomeDescrition');
insert into GroupList values('GroupName3','NO','False','SomeDescrition');
insert into GroupList values('GroupName4','NO','True','SomeDescrition');
insert into GroupList values('GroupName4','NO','True','SomeDescrition');
insert into GroupList values('GroupName4','YES','False','SomeDescrition');

然后

这是我在没有T-sql编辑器的情况下所能做的最好的了，希望这能有所帮助

除此之外：请看

---

好的，这是我给你的最好的，你仍然需要改变一两件事

假设：

create table GroupList (GroupName varchar(50),
                  LiveConnectEmailClosure varchar(50),
                  EnableSharing varchar(50),
                  GroupDescription varchar(50));

insert into GroupList values('GroupName1','YES','True','SomeDescrition');
insert into GroupList values('GroupName1','YES','True','SomeDescrition');
insert into GroupList values('GroupName1','NO','False','SomeDescrition');
insert into GroupList values('GroupName2','YES','True','SomeDescrition');
insert into GroupList values('GroupName2','YES','False','SomeDescrition');
insert into GroupList values('GroupName3','NO','True','SomeDescrition');
insert into GroupList values('GroupName3','NO','False','SomeDescrition');
insert into GroupList values('GroupName4','NO','True','SomeDescrition');
insert into GroupList values('GroupName4','NO','True','SomeDescrition');
insert into GroupList values('GroupName4','YES','False','SomeDescrition');

然后

这是我在没有T-sql编辑器的情况下所能做的最好的了，希望这能有所帮助

除此之外：请看

---

我喜欢第二个版本，它更接近我想要实现的目标。然而，它不起作用。请你把整个select语句都写下来好吗？我觉得我错过了什么。如果没有提供任何内容或提供的内容与列表中的内容不同，则标准应为“GroupName ASC”

ASC

需要在

CASE

语句的末尾。它不能混合搭配。我试过几种组合。你能写一个完整的select语句吗？我喜欢第二个版本，它更接近我想要实现的目标。然而，它不起作用。请你把整个select语句都写下来好吗？我觉得我错过了什么。如果没有提供任何内容或提供的内容与列表中的内容不同，则标准应为“GroupName ASC”

ASC

需要在

CASE

语句的末尾。它不能混合搭配。我试过几种组合。你能写一个完整的select语句吗？

SELECT
   CASE 
   WHEN xyz.something = 1 THEN 'SOMETEXT'
   WHEN xyz.somethingelse = 1 THEN 'SOMEOTHERTEXT'
   WHEN xyz.somethingelseagain = 2 THEN 'SOMEOTHERTEXTGOESHERE'
   ELSE 'SOMETHING UNKNOWN'
   END AS ColumnName;