Question

我正在尝试选择有nbre＆gt;的项目在此查询中为0：

SELECT c.id, c.nom, c.photo,
    (SELECT count(*) 
     FROM touist_materiel 
     WHERE cat=c.id AND marque=7 AND actif=1
    ) as nbre
FROM touist_materiel_cat c
INNER JOIN touist_materiel m ON m.cat=c.id 
WHERE nbre > 0 
GROUP BY m.cat 
ORDER BY c.nom

此查询不起作用，我怎样才能使用“where nbre＆gt; 0”？感谢

Answer 1

也许在没有子查询的情况下尝试？

SELECT c.id, c.nom, c.photo, count(m.*) AS nbre
FROM touist_materiel_cat c
INNER JOIN touist_materiel m
  ON m.cat=c.id AND m.marque=7 AND m.actif=1
GROUP BY m.cat
ORDER BY c.nom

使用INNER JOIN，我们总是有计数（m。*）＆gt; 0

Answer 2

SELECT tmc.id, tmc.nom, tmc.photo, count(tm.*) AS nbre
  FROM touist_materiel_cat tmc
  INNER JOIN touist_materiel tm
    ON tm.cat=tmc.id 
  WHERE nbre > 0 
    AND tm.marque=7 
    AND tm.actif=1
  GROUP BY tm.cat 
  ORDER BY tmc.nom;

Mysql选择count其中count＆gt; 0

2 个答案: