Question

How would I show, for example, the 10 most populous products in a table?

I have a sales table for example, that contains sales for 20 beers, 10 nachos, 5 peanuts, 2 hotdogs and 4 breakfasts.

Is there a way to automatically calculate and see which is the most popular, and show them in descending order?

edit:

My table is as follows

Tablename: sales

Fields:

• product (varchar)
• quantity (int)
• cost (decimal)
• saledate (date)

One sale record could count as more than one sale of a product, because of the quantity field.

I also have a guests table, which only has the fields name and country, and was wanting to show say, the top 5 most populous countries in the table.

Answer 1

Does this work for you?

select *
from(
  select count(productID) AS productCount, productName
  from products
  group by productID) Q
order by Q.productCount desc;

This counts the products in the inner query (it wasn’t clear if your table already stores counts, but it’s not common so I assumed you didn’t) and then orders them in the outer query.This also assumes your products have a productID field.

UPDATE

If your table actually tracks sales counts you could do something like this:

select *
from(
  select sum(quantity) AS productCount, productName
  from sales
  group by productID) Q
order by Q.productCount desc;

Very similar to the previous one but you are taking the sum of products sold from multiple sales items, rather than the count of products.