SELECT
p.ID PersonID,
STUFF(
(SELECT ';' + b.description
FROM personrole a
INNER JOIN role b
ON a.roleid = b.id
WHERE a.personid = p.id
FOR XML PATH (''))
, 1, 1, '') AS DescriptionList
FROM person AS p
GROUP BY p.ID
WYJŚCIE
╔══════════╦════════════════════════════╗
║ PERSONID ║ DESCRIPTIONLIST ║
╠══════════╬════════════════════════════╣
║ 1 ║ user ║
║ 2 ║ user;admininstrator;tester ║
╚══════════╩════════════════════════════╝