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create table yourtable (country varchar(100), value varchar(100));
insert into yourtable values ('FR',NULL);
insert into yourtable values ('FR',1);
insert into yourtable values ('FR',3);
insert into yourtable values ('MA',5);
insert into yourtable values ('MA',NULL);
insert into yourtable values ('MA',4);
insert into yourtable values ('ES',9);
insert into yourtable values ('ES',10);
insert into yourtable values ('ES',NULL);
9 rows affected
SELECT country, value FROM yourtable;
| country | value |
|---|---|
| FR | null |
| FR | 1 |
| FR | 3 |
| MA | 5 |
| MA | null |
| MA | 4 |
| ES | 9 |
| ES | 10 |
| ES | null |
SELECT country, STRING_AGG(COALESCE(value,'NULL'),',') AS value
FROM yourtable
GROUP BY country
ORDER BY country;
| country | value |
|---|---|
| ES | 9,10,NULL |
| FR | NULL,1,3 |
| MA | 5,NULL,4 |