So, I want to combine the two tables...
you don't really need to combine the two tables.
what you want is to find the customer that buys the most ingredients, then sort them in descending order with the biggest customer at the top.
to do this you will need a query that joins the two tables, but it doesn't merge them. merge is separate thing. all you need is a simple SELECT query with a left join that counts how many ingredients each customer buys...
Code:
SELECT tbl_customer.customer, Count(tbl_ingredient.customer) AS ingredients
FROM tbl_customer LEFT JOIN tbl_ingredient ON tbl_customer.customer = tbl_ingredient.customer
GROUP BY tbl_customer.customer
ORDER BY Count(tbl_ingredient.customer) DESC;
something like that.
many thanks,
Cottonshirt