How to get multiple rows into one line as a string?

Question

I have two tables \"one to many\":

Table1

ID    Name
1     Abe
2     David
3     Orly

Table2

ID    email
1     a@zz         


        

Answer 1

SELECT  *
FROM    Table1 a
CROSS APPLY --or OUTER APPLY
(
    SELECT SUBSTRING(
        (SELECT ','+b.Email
        FROM    Table2 b
        WHERE   a.ID = b.ID
        FOR XML PATH(''))
        ,2
        ,4000) GroupConcat
) x

Results:

ID Name  GroupConcat
-- ----- -----------------------------
1  Abe   a@zz.com,ab@zz.com,abe@zz.com
2  David dav@zz.com,d@zz.com
3  Orly  orly@zz.com,o@zz.com

Answer 2

One of the neatest ways to achieve this is to combine For XML Path and STUFF as follows:

SELECT
    ID, Name, 
    Emails = STUFF((
        SELECT ', ' + Email FROM Table2 WHERE Table2.ID = Table1.ID
        FOR XML PATH ('')),1,2,'')
FROM Table1