SQL Server : GROUP BY clause to get comma-separated values [duplicate]

The original data

ID    ReportId     Email
1     1            a@a.com
2     2            b@b.com
3     1            c@c.com
4     3            d@d.com
5     3            e@e.com

I want to group by ReportId, but all the email should be comma separated. So the result should be:
ReportId     Email
1            a@a.com, c@c.com
2            b@b.com
3            d@d.com, e@e.com


SELECT ReportId, Email = 
    STUFF((SELECT ', ' + Email
           FROM your_table b 
           WHERE b.ReportId = a.ReportId 
          FOR XML PATH('')), 1, 2, '')
FROM your_table a
GROUP BY ReportId

Hope this help !

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