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
关键
- regardless if there is an address for each of those people
解法：
SELECT p.FirstName, p.LastName, a.City, a.State
FROM
Person p
LEFT JOIN Address a ON p.PersonId = a.PersonId;