comma separated string of selected values in mysql

Question

I want to convert selected values into a comma separated string in MySQL. My initial code is as follows:

SELECT id FROM table_level where parent_id=4; 

Which produced:

'5' '6' '9' '10' '12' '14' '15' '17' '18' '779' 

My desired output would look like this:

"5,6,9,10,12,14,15,17,18,779" 

Answer 1

Check this

SELECT GROUP_CONCAT(id)  FROM table_level where parent_id=4 group by parent_id; 

Answer 2

If you have multiple rows for parent_id.

SELECT GROUP_CONCAT(id) FROM table_level where parent_id=4 GROUP BY parent_id; 

If you want to replace space with comma.

SELECT REPLACE(id,' ',',') FROM table_level where parent_id=4;