pg_rrule

pig build pkg pg_rrule;		# build rpm

pig repo add pgsql -u   # add both repo and update cache

pig install pg_rrule;		# install via package name, for the active PG version

pig install pg_rrule -v 18;   # install for PG 18
pig install pg_rrule -v 17;   # install for PG 17
pig install pg_rrule -v 16;   # install for PG 16
pig install pg_rrule -v 15;   # install for PG 15
pig install pg_rrule -v 14;   # install for PG 14

CREATE EXTENSION pg_rrule;

CREATE EXTENSION pg_rrule;

-- Get frequency
SELECT get_freq('FREQ=WEEKLY;INTERVAL=1;WKST=MO;UNTIL=20200101T045102Z'::rrule);
-- WEEKLY

-- Get days of week (numeric array)
SELECT get_byday('FREQ=WEEKLY;BYDAY=MO,TH,SU'::rrule);
-- {2,5,1}

-- Generate occurrences from an RRULE
SELECT unnest(get_occurrences(
    'FREQ=DAILY;INTERVAL=1;UNTIL=20200105T000000Z'::rrule,
    '2020-01-01 00:00:00'::timestamp
));