How Stuff and 'For Xml Path' work in Sql Server

Question

Table is:

+----+------+
| Id | Name |
+----+------+    
| 1  | aaa  |
| 1  | bbb  |
| 1  | ccc  |
| 1  | ffffd  |
| 1  | eee  |
+----+------+

Answer 1

STUFF((SELECT distinct ',' + CAST(T.ID) FROM Table T where T.ID= 1 FOR XML PATH('')),1,1,'') AS Name