Question

我想选择大多数事故中涉及哪种型号的汽车。我使用以下查询但我得到语法错误。请有人告诉我什么是错的..

    select car.Model 
    from car 
    join car_accident_involved 
       on car.Car_Registration_ID = car_accident_involved.Car_Registration_ID 
    group by car.Model 
    having MAX(
       select COUNT(Car_Registration_ID) 
       from car_accident_involved
    );

Answer 1

您可以在此处使用简单的子查询，例如：

select model from car
where car_registration_id = 
 (select car_registration_id
  from car_accident_involved
  group by model 
  order by count(car_registration_id) desc
  limit 1);

Answer 2

HAVING是GROUP BY的条件声明。您的查询中没有任何条件 HAVING声明，所以出现错误。对我来说，子查询中没有必要。尝试更简单的查询，如：

SELECT c.model,COUNT(a.car_registration_id) AS Num_of_accidents FROM car c   
INNER JOIN car_accident_involved a ON c.car_registration_id=a.car_registration_id  
GROUP BY c.model ORDER BY Num_of_accidents DESC LIMIT 1;

拥有Sub查询MySql

2 个答案: