如何在mysql中选择对应id的最大值
此查询返回按内部分组的所有评论,但id与此不对应。尝试以下操作:如何在mysql中选择对应id的最大值,mysql,Mysql,此查询返回按内部分组的所有评论,但id与此不对应。尝试以下操作: SELECT id , insId , MAX(avgRating) as avgRating FROM reviews WHERE status='1' GROUP BY insId 您需要使用自内部联接来获得所需的结果 SELECT id , insId , MAX(avgRating) as avgRating FROM reviews WHERE status='1' GR
SELECT
id
, insId
, MAX(avgRating) as avgRating
FROM reviews
WHERE status='1'
GROUP BY insId
您需要使用自内部联接来获得所需的结果
SELECT
id
, insId
, MAX(avgRating) as avgRating
FROM reviews
WHERE status='1'
GROUP BY id
您可以尝试以下方法:
SELECT
reviews.id
, reviews_max.insId
, reviews_max.maxAvgRating
FROM (
SELECT
insId
, MAX(avgRating) AS maxAvgRating
FROM
reviews
WHERE
status = '1'
GROUP BY
insId
) AS reviews_max
INNER JOIN
reviews
ON
reviews.insId = reviews_max.insId
AND
reviews.avgRating = reviews_max.maxAvgRating
试试GROUP_CONCAT(id)@DavidPartyka
GROUP_CONCAT(id)
将给出内部组中的所有id,这很可能不会生成正确的输出。它会选择所有评论,但我只想要最大值,这样对我不起作用。这一个选择具有重复的内部如何在这里获得不同的内部?什么MySQL版本@库玛
SELECT id,
insId,
MAX(avgRating) as avgRating
FROM reviews
WHERE status='1'
GROUP BY id, insId