MySQL按时间统计每个小时记录数 方案1: ? 1 2 3 4 5 6 7 SELECT @rownum := @rownum + 1 AS ID, CONCAT((CASE WHEN t.hour = 24 THEN 0 ELSE t.hour END),':00:00') AS TIME, COUNT(*) AS COUNT FROM (SELECT id, HOUR(DATE_FORMAT(createtime,'%H:%i:%s'))+1 AS HOUR FROM b
如下所示,引入<time.h>我们就可以统计时间了: #include<iostream> #include<time.h> #include<windows.h> using namespace std; int main() { time_t start, end; double cost; time(&start); for (int i = 0; i < 1000000000; i++) { int j = 0; j++; int k