如何将此Sql列连接成单个单元格？

Question

ClassName BookCode 
First   2 
Second   2 
Third   2 
First   3 
Fourth   3 
Fifth   3 

我想连接到这一点是这样的：

ClassName    BookCode 
First,Second,Third  2 
First,Fourth,Fifth  3 

Answer 1

试试这个

SELECT 
Distinct BookCode, 
    (
     SELECT ClassName +',' 
     FROM table1 t2 
     WHERE t2.BookCode= t1.BookCode 
     FOR XML PATH('') 
    ) Concatenated 

FROM table1 t1 

输出：

WORKING FIDDLE

Answer 2

尝试此查询：

select distinct t1.BookCode, 
    STUFF((SELECT distinct ',' + t2.ClassName 
     from yourtable t2 
     where t1.BookCode = t2.BookCode 
      FOR XML PATH(''), TYPE 
     ).value('.', 'NVARCHAR(MAX)') 
    ,1,0,',') ClassName 
from yourtable t1; 

未经测试。