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how to count of model of car

Person Table

ID FirstName  LastName PersonalWealth
1  Hello      Alest    $10,000.00
2  Leeds      United   $20,000.00
3  Middle     Brough   $30,000.00
4  Arsenal    Chelsey  $40,000.00
5  Manchester United   $50,000.00
6  Peter      Mean     $60,000.00
7  Hello      Coward   $60,000.00

Car Table

ID  CarRego  Model   Make   Manufacture  Year PersonID
1   abc123   Van            Toyota       2001 1
2   abc234   Ute            Honda        2005 1
3   pio345   Hatchback      Mitsubishi   1990 2
4   elf234   Hatchback      Ford         1996 3
5   flo124   Hatchback      Toyota       1992 4
6   asc234   hatchback      Holden       1965 6
7   xyz      hatchback      Holden       1998 5
8   avc      Van            jhjhjkhk     1989 1 

Here is the SQL code that i have

SELECT
  Count(Car.ID) AS CountOfid1, 
  Car.Model
FROM person
INNER JOIN Car ON person.ID=Car.ID
GROUP BY Car.Model; 

But it works with van saying 2 of them but in real there is 开发者_运维知识库only one owner how do i fix this?

Help would be much appreciated


Youl have to be a little more clear in your question ,im not sure what you want to achieve! if there is one owner per car then maybe setting the PK of car to owner then you ensure only own owner/car. That way you will never have dupe owners cos the pk will clash and youl get a PK exception if you try to add.


I am having a lot of trouble following this question but i see one clear problem

INNER JOIN Car ON person.ID=Car.ID

This does not make sense to me. I think what that line should read is

INNER JOIN Car ON person.ID=Car.OwnerID

Comparing primary keys to primary keys means nothing


here is the database for car

ID  CarRego  Model   Make   Manufacture  Year PersonID
1   abc123   Van            Toyota       2001 1
2   abc234   Ute            Honda        2005 1
3   pio345   Hatchback      Mitsubishi   1990 2
4   elf234   Hatchback      Ford         1996 3
5   flo124   Hatchback      Toyota       1992 4
6   asc234   hatchback      Holden       1965 6
7   xyz      hatchback      Holden       1998 5
8   avc      Van            jhjhjkhk     1989 1 
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