Question

SELECT v.*, COUNT(a.*) 
FROM vacancies AS v, applications AS a 
WHERE a.vacancy_id = v.id

Basically I need a way of counting the number of applications that correspond to each vacancy.

Applications have a vacancy id. So I want to get the vacancies from the vacancies table and iterate through them outputting the amount of applications that have the same vacancy_id.

Is this the right way to do it? It says I have a problem with the COUNT(a.*) bit.

Any ideas?

Thank you.

Edit

Ok, so I tried the group by thing, and now have this:

SELECT v.*, COUNT(a.candidate_id)
FROM vacancies AS v, applications AS a 
WHERE a.vacancy_id=v.id 
GROUP BY v.title

But it only returns one result, because theres only one application. Is there any way to return EVERYTHING from the vacancies table, even if there are no applications associated with the vacancy?

Answer 1

COUNT is a group operation. You need to use GROUP BY at the end.

EDIT
Use left join

SELECT v.*, COUNT(a.candidate_id)
FROM vacancies AS v
LEFT JOIN applications AS a on a.vacancy_id=v.id
GROUP BY v.title