SQL : count(*) NULL Résolu/Fermé

Question

Bonjour,
j'ai un souci avec une requete SQL
voici la requete:
SELECT count(DISTINCT a.id), count(DISTINCT b.id) , count(DISTINCT c.id), count(DISTINCT d.id) 
FROM 
(SELECT id FROM table WHERE prj_id="18" AND status="10") a,
(SELECT id FROM table WHERE prj_id="18" AND status="15") b,
(SELECT id FROM table WHERE prj_id="18" AND status="20") c,
(SELECT id FROM table WHERE prj_id="18" AND status="40") d

Mon souci c'est que si une des requetes de la clause FROM (a->d) ne retourne aucune valeur
alors tous mes count sont egale a 0

Comment contourner ce probleme?

D'avance merci.

Stef60 · Accepted Answer

j'ai trouvé la solution.

SELECT  a.cnt
    ,   b.cnt
    ,   c.cnt
    ,   d.cnt
FROM    (   SELECT  COUNT(DISTINCT id) AS cnt 
            FROM    matable 
            WHERE   prj_id='18' 
                AND STATUS='10'
        ) AS a
    ,   (   SELECT  COUNT(DISTINCT id) AS cnt 
            FROM    matable 
            WHERE   prj_id='18' 
                AND STATUS='15'
        ) AS b
    ,   (   SELECT  COUNT(DISTINCT id) AS cnt 
            FROM    matable 
            WHERE   prj_id='18' 
                AND STATUS='20'
        ) AS c
    ,   (   SELECT  COUNT(DISTINCT id) AS cnt 
            FROM    matable 
            WHERE   prj_id='18' 
                AND STATUS='40'
        ) AS d

WinGs · Answer

essaye en rajoutant IS NOT NULL dans tes SELECT a->d

Stef60 · Answer

J'ai essayé avec ca:
....
(SELECT id IS NOT NULL FROM table WHERE prj_id="18" AND status="10") a,
....

et ca me repond "Unknown column 'a.id' in 'field list'"

SQL : count(*) NULL

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