SQL Query for aggregation/concatenation

问题

I have a table like this:

ID    Name
----------
1   john
1   molly
2   greg
2   sean
1   holly
2   mill

What should the SQL Query be to aggregate results like the following:

ID  Name
-------------
1   john/molly/holly
2   greg/sean/mill

回答1:

Note: The STUFF function simply removes the leading / from the string returned.

SELECT t1.id, 
       STUFF((SELECT '/' + t2.name
                FROM YourTable t2
                WHERE t1.id = t2.id
                ORDER BY t2.name
                FOR XML PATH('')),1,1,'') AS Name
    FROM YourTable t1
    GROUP BY t1.id

来源：https://stackoverflow.com/questions/7896239/sql-query-for-aggregation-concatenation