SELECT id具有最大ID数

Question

有一个带有item_id和color_id的product表.我正在尝试使用大多数非null实例获取color_id.

这失败了:

SELECT color_id 
  FROM products 
 WHERE item_id=1234 
 GROUP BY item_id 
HAVING MAX(COUNT(color_id))

同

Invalid use of group function

这个

SELECT color_id, COUNT(color_id)
  FROM products 
 WHERE item_id=1234 
 GROUP BY item_id

返回

color_id count
1, 323
2, 122
3, 554

我正在寻找具有最多实例的color_id 3.

有没有2个查询可以快速简便地获得我想要的东西？

Answer 1

SELECT color_id AS id, COUNT(color_id) AS count 
FROM products 
WHERE item_id = 1234 AND color_id IS NOT NULL 
GROUP BY color_id 
ORDER BY count DESC
LIMIT 1;

这将为您提供color_id和color_id的计数,计数从最大到最小排序.我想这就是你想要的.

为你的编辑...

SELECT color_id, COUNT(*) FROM products WHERE color_id = 3;

Answer 2

SELECT color_id
FROM
    (
        SELECT  color_id, COUNT(color_id) totalCount
        FROM    products 
        WHERE   item_id = 1234 
        GROUP   BY color_id 
    ) s
HAVING totalCount = MAX(totalCount)

更新1

SELECT  color_id, COUNT(color_id) totalCount
FROM    products 
WHERE   item_id = 1234 
GROUP   BY color_id 
HAVING  COUNT(color_id) =
(
  SELECT  COUNT(color_id) totalCount
  FROM    products 
  WHERE   item_id = 1234 
  GROUP   BY color_id 
  ORDER BY totalCount DESC
  LIMIT 1  
)

• SQLFiddle演示(有领带)