Q&A for speakers of other languages learning English
select pr.OwnerUserId,STRING_AGG(CAST(pt.Tags AS VARCHAR(MAX)),'') as Tags from Posts q,Posts a ,Posts pr,Posts pt where q.Id = a.ParentId and a.OwnerUserId = pr.OwnerUserId and pr.PostTypeId = 2 and pr.ParentId = pt.Id and pt.PostTypeId = 1 and q.Id = 27729802 and q.PostTypeId = 1 group by pr.OwnerUserId