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https://github.com/timescale/timescaledb.git
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8be54d759d
This commit reduces the number of tuples added to the hyperstore table to reduce the runtime and also fixes `hyperstore_scans`. For `hyperstore_scans` it is necessary to reduce the number of locations since we want to trigger dictionary compression and make sure that it works for that as well.
70 lines
2.8 KiB
SQL
70 lines
2.8 KiB
SQL
-- This file and its contents are licensed under the Timescale License.
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-- Please see the included NOTICE for copyright information and
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-- LICENSE-TIMESCALE for a copy of the license.
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\ir include/setup_hyperstore.sql
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-- Set parallel cost to zero to force parallel plans and avoid flaky test.
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set parallel_tuple_cost to 0;
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set parallel_setup_cost to 0;
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-- We need to drop the index to trigger parallel plans. Otherwise they
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-- will use the index.
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drop index hypertable_device_id_idx;
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-- Show parallel plan and count on uncompressed (non-hyperstore)
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-- hypertable
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set max_parallel_workers_per_gather=2;
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select explain_anonymize(format($$
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select device_id, count(*) from %s where device_id=1 group by device_id
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$$, :'hypertable'));
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select device_id, count(*) from :hypertable where device_id=1 group by device_id;
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-- Save counts collected over entire hypertable
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select device_id, count(*) into orig from :hypertable group by device_id;
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-- Save counts over a single chunk
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select device_id, count(*) into orig_chunk from :chunk1 group by device_id;
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-----------------------
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-- Enable hyperstore --
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-----------------------
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select compress_chunk(show_chunks(:'hypertable'), compress_using => 'hyperstore');
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-- Show count without parallel plan and without ColumnarScan
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set timescaledb.enable_columnarscan=false;
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set max_parallel_workers_per_gather=0;
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select explain_anonymize(format($$
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select device_id, count(*) from %s where device_id=1 group by device_id
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$$, :'hypertable'));
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select device_id, count(*) from :hypertable where device_id=1 group by device_id;
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-- Enable parallel on SeqScan and check for same result
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set max_parallel_workers_per_gather=2;
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select explain_anonymize(format($$
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select device_id, count(*) from %s where device_id=1 group by device_id
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$$, :'hypertable'));
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select device_id, count(*) from :hypertable where device_id=1 group by device_id;
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-- Enable ColumnarScan and check for same result
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set timescaledb.enable_columnarscan=true;
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select explain_anonymize(format($$
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select device_id, count(*) from %s where device_id=1 group by device_id
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$$, :'hypertable'));
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select device_id, count(*) from :hypertable where device_id=1 group by device_id;
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-- Parallel plan with hyperstore on single chunk
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select explain_anonymize(format($$
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select device_id, count(*) from %s where device_id=1 group by device_id
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$$, :'hypertable'));
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select device_id, count(*) from :chunk1 where device_id=1 group by device_id;
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-- Compare hyperstore per-location counts with original counts without
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-- hyperstore
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select device_id, count(*) into comp from :hypertable group by device_id;
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select * from orig join comp using (device_id) where orig.count != comp.count;
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-- Compare counts on single chunk
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select device_id, count(*) into comp_chunk from :chunk1 group by device_id;
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select * from orig_chunk join comp_chunk using (device_id) where orig_chunk.count != comp_chunk.count;
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