On 1/19/25 12:09, Brent Wood wrote:
Thanks for the replies, appreciated...
My current solution is:
/select trip_code,/
/ station_no,/
/ timer_sec + interval '12 hour' as NZST,/
/ timer_sec as utc,/
/ hstore_to_json(string_agg(values_sec::text, ', ')::hstore)
as values_sec/
/ from (select '$TRIP' as trip_code,/
/ $STATION as station_no,/
/ date_trunc('second', timer) as timer_sec,/
/ values_sec/
/ from t_reading_hstore_sec/
/ where timer >= '$ISO_S'::timestamp - interval '12 hour'/
/ and timer <= '$ISO_F'::timestamp - interval '12 hour') as foo/
/group by timer_sec, trip_code, station_no;/
Convert the hstore to text, aggregate the text with string_agg(),
convert back to hstore (which seems to remove duplicate keys, OK for my
purpose)
To be clear values_sec in t_reading_hstore_sec is the hstore field?
If so what is it's structure?
and group by timer truncated to whole seconds. I also provide UTC &
local timezone times for each set of readings. It is run in a bash
script which passes the trip & station values to the query, as well as
the start/finish times as ISO format strings.
The output is going to a Sqlite3 (Spatialite) database, which does not
have hstore, or all the hstore functionality that Postgres has, but does
have a json datatype which is adequate for our purposes, hence the
hstore_to_json in the query.
Thanks again,
Brent Wood
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
