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9c9cdca6d3
Users can now (optionally) set a target chunk size and TimescaleDB
will try to adapt the interval length of the first open ("time")
dimension in order to reach that target chunk size. If a hypertable
has more than one open dimension, only the first one will have a
dynamically adapting interval.
Users can optionally specify their own function that calculates the
new dimension interval. They can also set a target size of 0 in order
to estimate a suitable target size for a chunk based on available
memory.
33 lines
1.5 KiB
SQL
33 lines
1.5 KiB
SQL
CREATE OR REPLACE FUNCTION _timescaledb_internal.dimension_calculate_default_range_open(
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dimension_value BIGINT,
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interval_length BIGINT,
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OUT range_start BIGINT,
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OUT range_end BIGINT)
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AS '@MODULE_PATHNAME@', 'dimension_calculate_open_range_default' LANGUAGE C STABLE;
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CREATE OR REPLACE FUNCTION _timescaledb_internal.dimension_calculate_default_range_closed(
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dimension_value BIGINT,
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num_slices SMALLINT,
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OUT range_start BIGINT,
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OUT range_end BIGINT)
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AS '@MODULE_PATHNAME@', 'dimension_calculate_closed_range_default' LANGUAGE C STABLE;
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-- Built-in function for calculating the next chunk interval when
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-- using adaptive chunking. The function can be replaced by a
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-- user-defined function with the same signature.
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--
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-- The parameters passed to the function are as follows:
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--
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-- dimension_id: the ID of the dimension to calculate the interval for
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-- dimension_coord: the coordinate / point on the dimensional axis
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-- where the tuple that triggered this chunk creation falls.
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-- chunk_target_size: the target size in bytes that the chunk should have.
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--
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-- The function should return the new interval in dimension-specific
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-- time (ususally microseconds).
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CREATE OR REPLACE FUNCTION _timescaledb_internal.calculate_chunk_interval(
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dimension_id INTEGER,
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dimension_coord BIGINT,
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chunk_target_size BIGINT
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) RETURNS BIGINT AS '@MODULE_PATHNAME@', 'calculate_chunk_interval' LANGUAGE C;
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