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d7b6ad239b
This PR adds support for finalizing aggregates with FINALFUNC_EXTRA. To do this, we need to pass NULLS correspond to all of the aggregate parameters to the ffunc as arguments following the partial state value. These arguments need to have the correct concrete types. For polymorphic aggregates, the types cannot be derived from the catalog but need to be somehow conveyed to the finalize_agg. Two designs were considered: 1) Encode the type names as part of the partial state (bytea) 2) Pass down the arguments as parameters to the finalize_agg In the end (2) was picked for the simple reason that (1) would have increased the size of each partial, sometimes considerably (esp. for small partial values). The types are passed down as names not OIDs because in the continuous agg case using OIDs is not safe for backup/restore and in the clustering case the datanodes may not have the same type OIDs either.
61 lines
2.8 KiB
SQL
61 lines
2.8 KiB
SQL
-- This file and its contents are licensed under the Apache License 2.0.
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-- Please see the included NOTICE for copyright information and
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-- LICENSE-APACHE for a copy of the license.
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-- This file is meant to contain aggregate functions that need to be created only
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-- once and not recreated during updates.
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-- There is no CREATE OR REPLACE AGGREGATE which means that the only way to replace
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-- an aggregate is to DROP then CREATE which is problematic as it will fail
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-- if the previous version of the aggregate has dependencies.
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-- NOTE that WHEN CREATING NEW FUNCTIONS HERE you should also make sure they are
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-- created in an update script so that both new users and people updating from a
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-- previous version get the new function
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--This aggregate returns the "first" element of the first argument when ordered by the second argument.
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--Ex. first(temp, time) returns the temp value for the row with the lowest time
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CREATE AGGREGATE first(anyelement, "any") (
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SFUNC = _timescaledb_internal.first_sfunc,
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STYPE = internal,
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COMBINEFUNC = _timescaledb_internal.first_combinefunc,
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SERIALFUNC = _timescaledb_internal.bookend_serializefunc,
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DESERIALFUNC = _timescaledb_internal.bookend_deserializefunc,
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PARALLEL = SAFE,
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FINALFUNC = _timescaledb_internal.bookend_finalfunc,
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FINALFUNC_EXTRA
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);
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--This aggregate returns the "last" element of the first argument when ordered by the second argument.
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--Ex. last(temp, time) returns the temp value for the row with highest time
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CREATE AGGREGATE last(anyelement, "any") (
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SFUNC = _timescaledb_internal.last_sfunc,
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STYPE = internal,
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COMBINEFUNC = _timescaledb_internal.last_combinefunc,
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SERIALFUNC = _timescaledb_internal.bookend_serializefunc,
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DESERIALFUNC = _timescaledb_internal.bookend_deserializefunc,
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PARALLEL = SAFE,
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FINALFUNC = _timescaledb_internal.bookend_finalfunc,
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FINALFUNC_EXTRA
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);
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-- This aggregate partitions the dataset into a specified number of buckets (nbuckets) ranging
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-- from the inputted min to max values.
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CREATE AGGREGATE histogram (DOUBLE PRECISION, DOUBLE PRECISION, DOUBLE PRECISION, INTEGER) (
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SFUNC = _timescaledb_internal.hist_sfunc,
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STYPE = INTERNAL,
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COMBINEFUNC = _timescaledb_internal.hist_combinefunc,
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SERIALFUNC = _timescaledb_internal.hist_serializefunc,
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DESERIALFUNC = _timescaledb_internal.hist_deserializefunc,
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PARALLEL = SAFE,
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FINALFUNC = _timescaledb_internal.hist_finalfunc,
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FINALFUNC_EXTRA
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);
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CREATE AGGREGATE _timescaledb_internal.finalize_agg(agg_name TEXT, inner_agg_collation_schema NAME, inner_agg_collation_name NAME, inner_agg_input_types NAME[][], inner_agg_serialized_state BYTEA, return_type_dummy_val anyelement) (
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SFUNC = _timescaledb_internal.finalize_agg_sfunc,
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STYPE = internal,
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FINALFUNC = _timescaledb_internal.finalize_agg_ffunc,
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FINALFUNC_EXTRA
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);
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