Example 1:
Select * from customers

Example 2:
select * from customers where Country ='uk'

Example 3:
select City,Country from customers order by city

Example 4:
select City,Country from customers order by 1

Example 5:
select distinct City,Country from customers order by 1

Example 6:
Select Count(*) from Customers where Country ='uk

Example 7:
Select sum(Quantity) from[order details] where productid = 11

Example 8:
Select productid, sum(Quantity) as sum_qty from [Order Details] group by productid