Слабая типизированность языка JavaScript подразумевает приведение обеих переменных к одному типу для того, чтобы произвести сравнение.
console.log(2 == true); // false. int boolean
console.log(!!2 == true); // true. boolean boolean
console.log(2 ? true : false); // true. boolean
CREATE TABLE IF NOT EXISTS `test1` (
`minVal` int(11) NOT NULL,
`maxVal` int(11) NOT NULL,
`price` int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`price`),
UNIQUE KEY `froms` (`minVal`),
UNIQUE KEY `fr2` (`minVal`,`maxVal`)
) ENGINE=MyISAM;
EXPLAIN SELECT *
FROM `test1`
WHERE minval <=42000
ORDER BY minval DESC
LIMIT 1
EXPLAIN SELECT *
FROM `test1`
WHERE minval <=42000
AND maxval >=42000
select CategoryId,max(id_min_value),max(id_max_value)
from
(select CategoryId,
case when ItemValue=min(ItemValue) over (partition by CategoryId) then ItemId end as id_min_value,
case when ItemValue=max(ItemValue) over (partition by CategoryId) then ItemId end as id_max_value
from Items) Items
group by CategoryId
SELECT CatsMMV.CategoryId, CatsMMV.MinV, CatsMMV.MaxV, MinI.ItemId AS MinItemID, MaxI.ItemId AS MaxItemID
FROM (SELECT CategoryId, MIN(ItemValue) AS MinV, MAX(ItemValue) AS MaxV
FROM Items
GROUP BY CategoryId) AS CatsMMV LEFT OUTER JOIN
Items AS MaxI ON CatsMMV.CategoryId = MaxI.CategoryId AND CatsMMV.MaxV = MaxI.ItemValue LEFT OUTER JOIN
Items AS MinI ON CatsMMV.CategoryId = MinI.CategoryId AND CatsMMV.MinV = MinI.ItemValue
SELECT U.*, S.*
FROM `user` AS U
LEFT JOIN stats AS S
ON S.user_id = u.ID
AND s.date = (
SELECT max(date)
FROM stats AS S2
WHERE s2.user_id = u.id
)
SELECT user.ud, MAX(stats.date) FROM user LEFT JOIN stats ON stats.user_id = user.id
