Convert this statement to sql query

Question

Display the package number and the number of customers for each package number, only for packages with more than 100 customers.

SELECT pack_num, COUNT(customer) 
FROM table_name 
GROUP BY pack_num
HAVING COUNT(customer) >100

Is this query right? If not please correct me.

Answer 1

To count only the unique costumers you could add a DISTINCT to the COUNT .

SELECT pack_num, COUNT(DISTINCT customer) 
FROM table_name 
GROUP BY pack_num
HAVING COUNT(DISTINCT customer) >100