Tutorial 6
More multi-table queries and
aggregates
Tutorial 5 and 6 objectives
• Displaying Data from Multiple Tables
– [ ]Write SELECT statements to access data from
more than one table using equality and non-equality
joins
– [ ]View data that generally does not meet a join
condition by using outer joins
– [ ]Join a table to itself using a self-join
• Aggregating Data using Group Functions
– [ ]Identify the available group functions
– [ ]Use group functions
– [ ]Group data using the GROUP BY clause [ ]Include
or exclude grouped rows by using the HAVING clause
Tutorial 6
[ ]Write SELECT statements to access data from
more than one table using equality and nonequality joins (see tutorial 5)
[ ]View data that generally does not meet a join
condition by using outer joins
O1
[ ]Join a table to itself using a self-join
O3
[ ]Identify the available group functions
O4
[ ]Use group functions
O5
[ ]Group data using the GROUP BY clause
O6
[ ]Include or exclude grouped rows by using the
HAVING clause
O7
O2
Using Northwind…
– Show the customerID, company name and orderId of
all customers.(O2)
– Show the CustomerId, companyname and OrderId of
all customers who do not have orders (O2).
– Show the lastname and title of all employees (worker)
who report to another employee (boss), along with the
boss’s last name (O3).
– (O4)[ ]Identify the available group functions
• Min(), max(), sum(), avg(), count(), count(*)
– (O5)[ ]Use group functions
•
•
•
•
•
•
•
Find the most expensive item in stock
Find the least expensive item in stock
Find the total value of all stock in stock
Count the number of types of products in stock.
Count the number of countries the employees come from.
Find the average number of units we hold in stock.
Count the employees from each country.
– (O6)[ ]Group data using the GROUP BY clause
• List all employee titles and the number of employees who have that
title.
– (O7)Include or exclude grouped rows by using the HAVING
clause
• List all suppliers who supply 2 or more products and the number of
products they supply.
Northwind data model
Testing the joins
select customers.customerId,
CompanyName, orderId from
customers left join orders on
customers.customerID=orders.customerID
where orders.customerID is null
Tugas Individu
1. Kunjungi
http://www.w3schools.com/sql/default.asp
2. Membuat ringkasan hasil kunjungan
ke URL di atas.