mysql - 如何比较where子句中的时间戳

Question

我有一个包含时间戳列的表，如果月份是 31 天，我想获取特定月份时间戳的值(例如 9 月 1 日到 9 月 30 日之间的时间戳)。 我使用这个查询:

SELECT users.username, users.id, count(tahminler.tahmin)as tahmins_no FROM users LEFT JOIN tahminler ON users.id = tahminler.user_id  GROUP BY users.id having count(tahminler.tahmin) > 0

我可以添加 where timestamp IN(dates_array) 吗？？

date_array 将是整个月的日期？？

Answer 1

SELECT users.username, users.id, count(tahminler.tahmin)as tahmins_no 
FROM users 
LEFT JOIN tahminler ON users.id = tahminler.user_id  
where year(timestamp) = 2013 and month(timestamp) = 9
GROUP BY users.id 
having count(tahminler.tahmin) > 0

To make it work with indexes you can do

SELECT users.username, users.id, count(tahminler.tahmin)as tahmins_no 
FROM users 
LEFT JOIN tahminler ON users.id = tahminler.user_id  
where timestamp >= '2013-09-01' and timestamp < '2013-10-01'
GROUP BY users.id 
having count(tahminler.tahmin) > 0