How to write sql statement for following scenario?

Question

So I currently have an sql statement:

Select room_no, category from help_desk where room_no = '133' OR room_no = '120';

and it returns:

How would I write an sql statement that would return it like this

Answer 1

You need to use three things

• GROUP BY
• GROUP_CONCAT
• DISTINCT within GROUP_CONCAT

Here is such a query

Select room_no, group_concat(distinct category) categories
from help_desk where room_no in (133,120) group by room_no;

Answer 2

You are looking for the group_concat feature.

Group Concat

For example:

SELECT room_no, GROUP_CONCAT(category)  
FROM help_desk 
GROUP BY room_no;