python sql 两时间相减,向下取整到天

import numpy as np
import pandas as pd
import datetime as dt

(data['time1'] - data['time2']).dt.days, 两时间相减,时间相减不满一天向下取整

select 等价 sql 

    datediff('day',time2,time1)

 这种只用时间中的日期计算

比如 time1 = 2020-10-25T11:43:04,time2 = 2020-09-21T14:34:43

datediff(time1,time2) = 34

 而 datediff('day',time2,time1) = 33