Question

I have a table that looks like this:

Pizza  ----|| Topping 
====================
Cheese--||    Olives
====================
Ham-----     || Tuna
====================
Cheese-- || Olives
====================
Cheese-- || Tuna
====================

I would like to obtain the number of pizzas of each type, so in the table above there would be one ham pizza, and 2 cheese pizzas (since cheese+olives is repeated and should be counted only once). Basically, I need to count each row for each two equal elements and group by pizza.

The result from that query should be:

Pizza  ----|| Count
====================
Cheese--||    2
====================
Ham-----     || 1
====================

Thanks!

Answer 1

select Pizza, count( distinct Topping) as cnt
from your_pizza_table
group by Pizza
order by cnt desc;