LeetCode 175 Combine Two Tables mysql,left join 难度:0
https://leetcode.com/problems/combine-two-tables/
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
select p.FirstName,p.LastName,a.City,a.State from Person as p left join Address as a on p.PersonId = a.PersonId;
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