import pandas as pd
import datetime
def trans_day(df_new,sn,start_time1,table_name,db_engine):
    end_t=pd.to_datetime(start_time1) -datetime.timedelta(seconds=600)
    sql="select * from  {}  where sn='{}' and  Time_e>='{}' ".format(table_name,sn,end_t)
    df_old=pd.read_sql_query(sql, db_engine)
    if len(df_old)>=1:
        df_old=df_old[["sn","Time_b","Time_e"]].iloc[-1,:]
        df_new=df_new[["sn","Time_b","Time_e"]].iloc[0,:]
        time_delta=abs(pd.to_datetime(df_new["Time_b"])- pd.to_datetime(df_old["Time_b"])).total_seconds()
        
        if time_delta<120:
            with db_engine.connect() as con:
                sql2="delete from  {}  where   sn='{}'   and  Time_b='{}' ".format(table_name,df_old["sn"],df_old["Time_b"])
                con.execute(sql2)
                con.connection.commit()