Group Concat MS SQL

 SELECT 

 T.orderItemId

 , STUFF(( SELECT ‘,’+(attribute_name+’: ‘+attribute_value) FROm  

Test_Staging.dbo.qtorderoptions where qtorderoptions.orderItemId =T.orderItemId

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

FROM

 Test_Staging.dbo.qtorderoptions As T

GROUP BY 

 T.orderItemId