sql 练习---连接某字段的值给一个字符串

有表A,

id Name

1 1

1 2

1 3

2 1

2 2

3 1

转化成表B:

id Name

1 1,2,3

2 1,2

3 1

------------------------------------------------------------------------
现接受两个方法,首先创建表

TEST
(
ID VARCHAR(36),
Name VARCHAR(36)
)
INSERT INTO TEST1 VALUES ('1',1)
INSERT INTO TEST1 VALUES ('1',2)
INSERT INTO TEST1 VALUES ('1',3)
INSERT INTO TEST1 VALUES ('2',1)
INSERT INTO TEST1 VALUES ('2',2)
INSERT INTO TEST1 VALUES ('3',1

------------------------------------------------------------------------

1 利用sql查询对结果集进行连接
声明一个函数，返回连接之后的字符串

   declare @str varchar(200)
   set @str=''
   select @str=@str+','+cast(Name as varchar) from TEST where id=@id
   set @str=right(@str,len(@str)-1)
   return(@str)

最后执行 SELECT DISTINCT ID,dbo. GetNameByID(ID) FROM TEST

2 利用游标来返回字符串

  DECLARE @Str VARCHAR(200)
  DECLARE @Name VARCHAR(200)
  DECLARE Name_cursor CURSOR FOR
  SELECT Name FROM Test1 Where ID=@ID
  OPEN Name_cursor
  FETCH NEXT FROM Name_cursor INTO @Str
  SET @Name=''
  WHILE(@@FETCH_STATUS=0)
  BEGIN
       SELECT @Name=@Name+','+@Str
       FETCH NEXT FROM Name_cursor INTO @Str
  END

  SELECT @Name=right(@Name,LEN(@Name)-1)
  CLOSE Name_cursor
  DEALLOCATE Name_cursor
  RETURN @Name

最后执行 SELECT DISTINCT ID,dbo. GetNameByID(ID) FROM TEST

Code