timescaledb/sql/aggregates.sql
Sven Klemm f89fd07c5b Remove year from SQL file license text
This changes the license text for SQL files to be identical
with the license text for C files.
2019-01-13 23:30:22 +01:00

53 lines
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SQL

-- This file and its contents are licensed under the Apache License 2.0.
-- Please see the included NOTICE for copyright information and
-- LICENSE-APACHE for a copy of the license.
-- This file is meant to contain aggregate functions that need to be created only
-- once and not recreated during updates.
-- There is no CREATE OR REPLACE AGGREGATE which means that the only way to replace
-- an aggregate is to DROP then CREATE which is problematic as it will fail
-- if the previous version of the aggregate has dependencies.
-- NOTE that WHEN CREATING NEW FUNCTIONS HERE you should also make sure they are
-- created in an update script so that both new users and people updating from a
-- previous version get the new function
--This aggregate returns the "first" element of the first argument when ordered by the second argument.
--Ex. first(temp, time) returns the temp value for the row with the lowest time
CREATE AGGREGATE first(anyelement, "any") (
SFUNC = _timescaledb_internal.first_sfunc,
STYPE = internal,
COMBINEFUNC = _timescaledb_internal.first_combinefunc,
SERIALFUNC = _timescaledb_internal.bookend_serializefunc,
DESERIALFUNC = _timescaledb_internal.bookend_deserializefunc,
PARALLEL = SAFE,
FINALFUNC = _timescaledb_internal.bookend_finalfunc,
FINALFUNC_EXTRA
);
--This aggregate returns the "last" element of the first argument when ordered by the second argument.
--Ex. last(temp, time) returns the temp value for the row with highest time
CREATE AGGREGATE last(anyelement, "any") (
SFUNC = _timescaledb_internal.last_sfunc,
STYPE = internal,
COMBINEFUNC = _timescaledb_internal.last_combinefunc,
SERIALFUNC = _timescaledb_internal.bookend_serializefunc,
DESERIALFUNC = _timescaledb_internal.bookend_deserializefunc,
PARALLEL = SAFE,
FINALFUNC = _timescaledb_internal.bookend_finalfunc,
FINALFUNC_EXTRA
);
-- This aggregate partitions the dataset into a specified number of buckets (nbuckets) ranging
-- from the inputted min to max values.
CREATE AGGREGATE histogram (DOUBLE PRECISION, DOUBLE PRECISION, DOUBLE PRECISION, INTEGER) (
SFUNC = _timescaledb_internal.hist_sfunc,
STYPE = INTERNAL,
COMBINEFUNC = _timescaledb_internal.hist_combinefunc,
SERIALFUNC = _timescaledb_internal.hist_serializefunc,
DESERIALFUNC = _timescaledb_internal.hist_deserializefunc,
PARALLEL = SAFE,
FINALFUNC = _timescaledb_internal.hist_finalfunc,
FINALFUNC_EXTRA
);