我想做的很简单我有一个充满start_times&finish_times。全部启动&除两行外,在同一天完成时间采用24小时格式
我想计算最小值,最大值,&计算出的持续时间的avg。问题出在230行中,其中2行经过时间重置。例如,一个开始时间是2020-10-14 23:37:26&其相应的结束时间为2020-10-15 00:19:47我还有一排,考试开始1天&完成下一个
我将值存储为DATETIME如何将其转换为我想要的输出?
SELECT AVG(SEC_TO_TIME(TIMESTAMPDIFF(MINUTE, Start_Time, Finish_Time))) AS
Avg_Exam_Duration,
MIN(SEC_TO_TIME(TIMESTAMPDIFF(MINUTE, Start_Time, Finish_Time))) AS
Min_Exam_Duration,
MAX(SEC_TO_TIME(TIMESTAMPDIFF(MINUTE, Start_Time, Finish_Time))) AS
Max_Exam_Duration,
Room_ID FROM exam
GROUP BY Room_ID;
期望的输出将正确地计算Max、Min和&时间之间持续时间(经过时间(的平均值
电流输出
代替:
TIMEDIFF(Finish_Time, Start_Time)
用途:
SEC_TO_TIME(TIMESTAMPDIFF(SECOND, Start_Time, Finish_Time))
(注意参数的变化顺序。(