175. Combine Two Tables

Table:Person

+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| PersonId    | int     |
| FirstName   | varchar |
| LastName    | varchar |
+-------------+---------+
PersonId is the primary key column for this table.

Table:Address

+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| AddressId   | int     |
| PersonId    | int     |
| City        | varchar |
| State       | varchar |
+-------------+---------+
AddressId is the primary key column for this table.

Write a SQL query for a report that provides the following information for each person in the Person table, regardless if there is an address for each of those people:

FirstName, LastName, City, State

Solution：

### 1. use LEFT JOIN
SELECT Person.FirstName, Person.LastName, Address.City, Address.State 
FROM Person 
LEFT JOIN Address 
ON Person.PersonId = Address.PersonId;

### 2. use keyword USING
SELECT Person.FirstName, Person.LastName, Address.City, Address.State 
FROM Person 
LEFT JOIN Address 
USING(PersionId);

Reference: