How do I join all values from multiple rows into a single row?

Answer 1

DECLARE @foos VARCHAR(4000)

SELECT @foos = COALESCE(@foos + ',', '') + Foo FROM Bar

SELECT @foos AS Foo

Answer 2

Ross,

this should get you started.

  DECLARE @r VARCHAR(8000)
  SELECT @r = (SELECT DISTINCT Foo + ', ' FROM Bar FOR XML PATH(''))
  IF @r IS NOT NULL AND @r <> '' SET @r = SUBSTRING(@r, 1, LEN(@r)-1)
  SELECT @r

Answer 3

Try the following

declare @joined varchar(max)
set @joined = ''

select  @joined = @joined + IsNull(Foo + ',', '')
from    Bar (nolock)

--; Drop last "," if necessary
set @joined = substring(@joined, 1, len(@joined) - (case when len(@joined) > 0 then 1 else 0 end))
select  @joined as foo

Answer 4

SELECT
    ( 
    SELECT
      CASE
        WHEN ROW_NUMBER() OVER(ORDER BY bar) = 1 THEN ''
        ELSE ', '
      END + CAST(bar AS VARCHAR)
    FROM foo
    ORDER BY bar
    FOR XML PATH('')
    )

Answer 5

 select max(a),max(b),max(c) from
 (
      select 'a' as a,null as b,null as c
      union
      select null,'b',null
      union
      select null,null,'c'
 ) as x