将sql的多行查询结果拼接成一个字符串

DECLARE @S VARCHAR(MAX)=
(  
  SELECT STUFF( (select distinct ','+CAST(C1 AS VARCHAR(20)) 
  FROM (
     SELECT 1 AS C1,2 AS C2 
     UNION ALL SELECT 3,5
   ) A 
   FOR XML PATH('')) , 1 , 1 , '' ))

SELECT @S='(''' + REPLACE(@S,',',''',''') + ''')'

SELECT @S

/*
  
------------------------------- 
('1','3')

(1 行受影响)

*/