Group Concat MS SQL

 SELECT TOP 1000

 T.orderItemId

 , STUFF(( SELECT ','+(attribute_name+': '+attribute_value) FROm qsorderoptions where qsorderoptions.orderItemId =T.orderItemId

   FOR XML PATH('')) , 1 , 1 , '' ) AS Feld               

FROM

 qsorderoptions As T

--GROUP BY  T.product_id

GROUP BY 

 T.orderItemId