Question

I need help to write a simple procedure. Let me explain what I’m trying to do.

I have 3 tables

1. tJobOffer
2. tApplication
3. tApplicationStatus

I would like to create a procedure that return me a list of tJobOffer with the statistics of different status of this tJobOffer. tApplicationStatus is linked to tApplication that is linked to tJobOffer. An application can be CANDIDATE / ACCEPTED / REFUSED / IGNORED / …

I created this query :

    SELECT 
        [T].[JobOfferId],
        [T].[JobOfferTitle],
        COUNT([A].[ApplicationId]) AS [CandidateCount]

    FROM        [tJobOffer] AS [T]
    LEFT JOIN   [tApplication] AS [A]
        INNER JOIN   [tApplicationStatus] AS [S]
            ON      [S].[ApplicationStatusId] = [A].[ApplicationStatusId]
            AND     [S].[ApplicationStatusTechnicalName] = 'CANDIDATE'
        ON      [A].[JobOfferId] = [T].[JobOfferId]

    GROUP BY
            [T].[JobOfferId],
            [T].[JobOfferTitle]

    ORDER BY [T].[JobOfferTitle] ;

The result is

> 52ED7C67-21E1-49BB-A1F8-0601E6EED1EA  Announce a  0
> F26B228D-0C81-4DA8-A287-F8F997CC1F9C  Announce b  0
> 9DA60B23-F113-4C7F-9707-2B90C1556D5D  Announce c  2
> 258E11A7-79C1-47B6-8C61-413AA54E2360  Announce d  0
> DA582383-5DF4-4E1D-837C-382371BDEF57  Announce e  1

The result is correct. I get my tJoboffers with statistic on status candidate. I have 2 candidates for Announce c and 1 candidate for announce e. If I change my string ‘CANDIDATE’ to ‘ACCEPTED’ or ‘REFUSED’ I can get the statistic on these status. Is it possible to get everything in one request?

Something like

> 52ED7C67-21E1-49BB-A1F8-0601E6EED1EA  Announce a  0   0   2
> F26B228D-0C81-4DA8-A287-F8F997CC1F9C  Announce b  0   0   1
> 9DA60B23-F113-4C7F-9707-2B90C1556D5D  Announce c  2   0   0
> 258E11A7-79C1-47B6-8C61-413AA54E2360  Announce d  0   0   0
> DA582383-5DF4-4E1D-837C-382371BDEF57  Announce e  1   1   0

Answer 1

use SUM and CASE

SELECT 
    [T].[JobOfferId],
    [T].[JobOfferTitle],
    SUM(CASE WHEN [S].[ApplicationStatusTechnicalName] = 'CANDIDATE' THEN 1 ELSE 0 END) AS [CandidateCount],
    SUM(CASE WHEN [S].[ApplicationStatusTechnicalName] = 'ACCEPTED' THEN 1 ELSE 0 END) AS [ACCEPTEDCount],
    SUM(CASE WHEN [S].[ApplicationStatusTechnicalName] = 'REFUSED' THEN 1 ELSE 0 END) AS [REFUSEDCount]
FROM    [tJobOffer] AS [T]
        LEFT JOIN   [tApplication] AS [A]
            ON      [A].[JobOfferId] = [T].[JobOfferId]
        LEFT JOIN   [tApplicationStatus] AS [S]
            ON      [S].[ApplicationStatusId] = [A].[ApplicationStatusId]
GROUP BY
        [T].[JobOfferId],
        [T].[JobOfferTitle]
ORDER BY [T].[JobOfferTitle] ;