Choosing a column that fulfills many conditions in different records

Question

I have got table like this:

+----------+---------+
| Customer | Product |
+----------+---------+
|        1 |       1 |
|        1 |       2 |
|        1 |               


        

Answer 1

if you want the customer who bought all the 3 product you could use aggregation function count(distinct product)

    SELECT Customer
    FROM your_table
    where product in (1,2,3)
    GROUP BY Customer
    HAVING count(distinct product) = 3