how to use Sql join left with 2 tables but table2 has many-to-one relation

Question

I got 2 tables in my db and i want to join them together but because sometime i got more than one record in table 2 that connect to table1 i want to show them in a new column. i have app in .net C# that send the query and read from it.

Table1:

id	name
1	James
2	Jane
3	Gil

Table2:

id	table1_id	countries_visited
1	1	USA
2	1	Germany
3	2	France

and i want the end result from the query to be:

id	name	country	country	....
1	James	USA	Germany	....
2	Jane	France	no column here
3	Gil	no more columns

my question is it possible to make rows have different columns? and if its not possible than have all rows max country colums ( changed by the max amount of country visted to single key ) and have null in their value.

ex:

id	name	country	country	....
1	James	USA	Germany	....
2	Jane	France	null	....
3	Gil	null	null	....

the.... represents if i had more countries to a single key.

maybe i got it all wrong but the reson i want this is because i can have some users with no countries visited and some with one or more without limiting.

Answer 1

You need to pivot on rownumber:

SELECT
    id,
    name,
    MIN(CASE WHEN rn = 1 THEN countries_visited END) country1,
    MIN(CASE WHEN rn = 2 THEN countries_visited END) country2,
    MIN(CASE WHEN rn = 3 THEN countries_visited END) country3,
    ......... etc copy paste as many as you need
FROM (
    SELECT t1.*, t2.countries_visited,
        ROW_NUMBER() OVER (PARTITION BY t1.ID ORDER BY t2.countries_visited) AS rn
    FROM Table1 t1
    JOIN Table2 t2 ON t2.table1_id = t1.id
) t
GROUP BY id, name;

You can also do this with the PIVOT keyword, but that is less flexible.