SQL Count Function By Column

Question

CusID   Order
3001    Hotdog
3001    Sausage
3002    Sausage
3003    Burger
3003    Hotdog
3002    Hotdog
3001    Burger

How I will use this count function?

SELECT COUNT(CusID) AS NumOfOrders FROM Orders

Desired output

CusID   NumOfOrders
3001    3
3002    2
3003    2

Answer 1

You need it with a group by:

SELECT CusId, COUNT(CusID) AS NumOfOrders
FROM Orders
group by CusId
order by CusId;

Answer 2

The group by will give you that desired result along with Count function.

select CustID, count(CustID) from Orders
group by CustID

Refer below fiddle link for sample

SQL Fiddle