INSERT...SELECT statement

[stefano.giorgetti]

I need to execute an INSERT...SELECT query.

INSERT HIGH_PRIORITY INTO stations_data
(station_id,
Tmin,
Tmax,
Tmed,
RHmin,
RHmax,
RHmed,
rain,
Wmax,
slpres,
insertion_date)
(
SELECT
stations.station_id AS stId,
min(stations_rt_data.T) AS tmax,
max(stations_rt_data.T) AS tmin,
avg(stations_rt_data.T) AS tmed,
min(stations_rt_data.RH) AS rhmin,
max(stations_rt_data.RH) AS thmax,
avg(stations_rt_data.RH) AS rhmed,
sum(stations_rt_data.rain) AS rain,
max(stations_rt_data.Wmax) AS wmax,
stations_rt_data.pres AS pres,
NOW() AS tempo
FROM (
stations INNER JOIN stations_rt_data ON stations.code = stations_rt_data.station_id
)
WHERE
stations_rt_data.observation_datetime_gmt
BETWEEN DATE_FORMAT('2005/01/21 > 00:00:00', '%Y%m%d%H%i%s')
AND DATE_FORMAT('2005/01/21 > 23:59:59', '%Y%m%d%H%i%s')
GROUP BY
stations_rt_data.station_id
)

It works fine for every value bt stations_rt_data.pres:it looks for all observations collected during the past 24 hours.
But I need to get the value of this field at a particular stations_rt_data.observation_datetime_gmt

Can I modify this query in order to get stations_rt_data.pres select for a particular stations_rt_data.observation_datetime_gmt leaving other fields selected as shown in the query WHERE part?

Thanks!