[LeetCode] 175. Combine Two Tables

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Problem

Table: Person

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

Table: Address

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+-------------+---------+
| 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:

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FirstName, LastName, City, State

Explanation

  1. We can use LEFT JOIN.

Solution

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# Write your MySQL query statement below
SELECT p.FirstName, p.LastName, a.City, a.State
FROM Person AS p LEFT JOIN Address AS a ON p.PersonId = a.PersonId;