Mysql average value every minute refer to unix timestamp

问题

I logging my temperature every 1-3 seconds with unix timestamp, I wish like get row of data return by average every 1 minute period and last for 24 hour.

my logger table look like this:

unixtime    temp
1350899052  25.37
1350899054  25.44
1350899057  25.44
1350899059  25.44
1350899062  25.44
1350899064  25.44
1350899069  25.44
1350899071  25.44

and i wish like it return as

unixtime    temp
1350899052  25.37 -- average value of 1 minute range both unixtime and temp 
1350899054  25.44
1350899057  25.44

please advise how is mySQL command should i do ? thank.

回答1:

The following should work:

SELECT ROUND(unixtime/(60)) AS minute, avg(temp) FROM table where unixtime >= UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 1 DAY)) GROUP BY ROUND(unixtime/(60));

Show date in normal format:

SELECT from_unixtime(floor(unixtime/(60))*60) AS minute, avg(temp) FROM test where unixtime >= UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 1 DAY)) GROUP BY floor(unixtime/(60))

outputs:

minute  avg(temp)
2012-10-24 08:02:00 37.5
2012-10-24 08:03:00 45

回答2:

 1. 1 min

select * from logger_table where unixtime> timestamp(DATE_SUB(NOW(), INTERVAL 1 MINUTE)) group by temp

 2. 24 hrs
select * from logger_table where unixtime> timestamp(DATE_SUB(NOW(), INTERVAL 24 HOUR)) group by temp;

来源：https://stackoverflow.com/questions/13043705/mysql-average-value-every-minute-refer-to-unix-timestamp