使用Clause mysql的嵌套计数？

Question

我想计算从不同类别中选择的图像，我的查询返回错误

  

＃1064 - 您的SQL语法出错;查看与您的MySQL服务器版本对应的手册，以便在'（选择计数（i1.id）作为cnt FROM image_gallery i1 LEFT OUTER JOIN image_g'在第2行附近使用正确的语法

我哪里错了？

SELECT count(*)
(select count(*)
FROM image_gallery i1
LEFT OUTER JOIN image_gallery i2
  ON (i1.category_id = i2.category_id AND i1.id < i2.id)
GROUP BY i1.id
HAVING COUNT(*) < 10 
) as total_pics

Answer 1

您错过了FROM关键字

SELECT sum(cnt)
FROM
(
  select count(i1.id) as cnt
  FROM image_gallery i1
  LEFT OUTER JOIN image_gallery i2 ON i1.category_id = i2.category_id 
                                  AND i1.id < i2.id
  GROUP BY i1.id
  HAVING COUNT(*) < 10 
) as total_pics