https://leetcode.com/problems/combine-two-tables/description/

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

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• Since the PersonId in table Address is the foreign key of table Person, we can join this two table to get the address information of a person. 

• Considering there might not be an address information for every person, we should use outer join instead of the default inner join.

• Note: Using where clause to filter the records will fail if there is no address information for a person because it will not display the name information.

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1 Create table If Not Exists Person (PersonId int, FirstName varchar(255), LastName varchar(255)); 2 Create table If Not Exists Address (AddressId int, PersonId int, City varchar(255), State varchar(255)); 3 Truncate table Person; 4 insert into Person (PersonId, LastName, FirstName) values ('1', 'Wang', 'Allen'); 5 Truncate table Address; 6 insert into Address (AddressId, PersonId, City, State) values ('1', '2', 'New York City', 'New York'); 7  8 # Write your MySQL query statement below 9 select P.FirstName, P.LastName, A.City, A.State 10 from Person P left join Address A 11 on P.PersonId = A.PersonId;