Is it possible to GROUP BY multiple columns using MySQL?

Question

GROUP BY col1, col2, col3

Yes, you can group by multiple columns. For example,

SELECT * FROM table
GROUP BY col1, col2

The results will first be grouped by col1, then by col2. In MySQL, column preference goes from left to right.

Yes, but what does grouping by more two columns mean? Well, it's the same as grouping by each unique pair per row. The order you list the columns changes the way the rows are sorted.

In your example, you would write

GROUP BY fV.tier_id, f.form_template_id

Meanwhile, the code

GROUP BY f.form_template_id, fV.tier_id

would give similar results, but sorted differently.

group by fV.tier_id, f.form_template_id