Sometimes you need to access two or more tables to get the
data required.
games
yr
city
1896
Athens
1948
London
2004
Athens
2008
Beijing
2012
London
city
name
country
Sydney
Australia
Athens
Greece
Beijing
China
London
UK
You can use a JOIN to get results from two or more related tables.
In this example each row of the table games is related to
a row of the table city.
If you want to find the country where the games took place
you must JOIN the games table to the city table on the
common field that is games.city and city.name