How to group two columns?

Question

SQL

Tell me how to write a query that displays the name of the state (state) in one column, in the second all the cities
(city) that are in this state.

Answer 1

MSSQL:

select state,
( select city+',' as 'data()' from dbo.test t2 where t1.state=t2.state for xml path('') )
from dbo.test t1
group by state

MySQL:

SELECT 
state,
GROUP_CONCAT(city)
FROM your_table
GROUP BY state

Answer 2

select state, group_concat(city separator ",") from ... group by state

dev.mysql.com/doc/refman/5.7/en/group-by-functions...

Answer 3

You have SQL Server, judging by the screenshot from SQL Server Management Studio. There is no group_concat(), the simplest solution can be found here: stackoverflow.com/questions/451415/simulating-grou...