[LeetCode]-DataBase-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


需求：简单的表连接

查询：sql

CREATE TABLE Person(
PersonId TINYINT UNSIGNED auto_increment PRIMARY KEY,
FirstName varchar(20),
LastName varchar(20)
)ENGINE=MyISAM CHARSET=utf8;
CREATE TABLE Address(
AddressId TINYINT UNSIGNED auto_increment PRIMARY KEY,
PersonId TINYINT UNSIGNED,
City VARCHAR(20),
State VARCHAR(20)
)ENGINE=MyISAM CHARSET=utf8;

SELECT t1.FirstName,t1.LastName,t2.City,t2.State
FROM Person t1
LEFT JOIN Address t2 ON t1.PersonId=t2.PersonId

[LeetCode]-DataBase-Combine Two Tables

原文：http://www.cnblogs.com/lianliang/p/5303037.html