SQL Conditionnement

Question

Je veux montrer le nom du département et le nombre de départements en dehors de l'Australie.

Le problème est que ce code ci-dessous donne encore un décompte incluant les départements en Australie. (Edit) - c'est plus proche de la solution mais pas encore tout à fait raison. - ne pas retourner le compte correct.

SELECT department_name, COUNT(COUNTRIES.country_id) 
FROM DEPARTMENTS, COUNTRIES 
JOIN (
    SELECT COUNT(COUNTRIES.country_name) AS COUNTRY 
    FROM COUNTRIES 
    JOIN DEPT_LOCATIONS ON COUNTRIES.country_id = DEPT_LOCATIONS.country_id 
    WHERE country_name <> 'Australia' 
    ) AS C ON COUNTRY = c.country 
    GROUP BY department_name; 

Voici le schéma de base de données:

COUNTRIES(country_id, country_name, region) 
• Primary key: {country_id} 

DEPARTMENTS(department_id, department_name, manager_id) 
• Primary key: {department_id } 
• Foreign key: [manager_id] ⊆ EMPLOYEES[employee_id] 

DEPT_LOCATIONS(department_id, city, country_id) 
• Primary key: {department_id, city} 
• Foreign key: [department_id] ⊆ DEPARTMENTS[department_id] and 
[country_id] ⊆ COUNTRIES[country_id] 

EMPLOYEES(employee_id, firstname, lastname, email, phone_no, salary, 
department_id) 
• Primary key: {employee_id} 
• Foreign key: [department_id] ⊆ DEPARTMENTS[department_id] 

Answer 1

Avez-vous essayé cette

SELECT department_name, COUNT(DEPT_LOCATIONS.country_id) 
FROM DEPARTMENTS 
LEFT JOIN DEPT_LOCATIONS ON DEPARTMENTS.department_id = DEPT_LOCATIONS.department_id  
GROUP BY department_name 
HAVING department_name <> 'Australia' 

Answer 2

figured it moi-même acclamations

SELECT department_name, COUNT(COUNTRIES.country_id) 
FROM DEPARTMENTS, COUNTRIES 
RIGHT JOIN DEPT_LOCATIONS ON DEPT_LOCATIONS.country_id = COUNTRIES.country_id 
WHERE DEPARTMENTS.department_id = DEPT_LOCATIONS.department_id 
AND country_name <> 'Australia' 
GROUP BY department_name;