Code Snippet:

1    USE world; 
2    SELECT ci.name AS "City Name",
3        co.name AS "Country Name", 
4        cl.language AS "Country Language" 
5    FROM city ci
6        JOIN country co 
7            ON ci.CountryCode = co.Code 
8        JOIN country language cl 
9            ON cl.CountryCode = ci.CountryCode;


Results:

JOIN countrylanguage cl.

• The “cl” is the alias for countrylanguage.
• You can refer to tables already specified in a previous join.

ON cl.CountryCode = ci.CountryCode;

• The common column between the two tables being joined is the CountryCode column from the countrylanguage table and the CountryCode column from the city table.
• The “cl” alias previously defined for countrylanguage is used to specify the CountryCode column.