SQL返回行，如果沒有結果發現

Question

我有兩個表：

person 
id 
name 

car 
name 
person_id 

目前查詢是這樣：

SELECT 
person.name 
car.name 
FROM 
person, car 
WHERE 
person.id = car.person_id 

現在如果有一個人相關聯的汽車能正常工作。但是，如果沒有，那麼這個人將不會得到回報。如果一個人沒有汽車，我想在列car.name中返回一行文字'No Car'。

Answer 1

select person.name, coalesce(car.name, 'no car') 
from person 
left outer join car on person.id = car.person_id 

Answer 2

select person.name, ISNULL(car.name, 'no car') 
from person 
left join car on person.id = car.person_id 

Answer 3

SELECT person.name, CASE WHEN car.name IS NULL THEN 'no car' ELSE car.name END 
FROM person 
LEFT JOIN car ON person.id = car.person_id