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6232f98edc
A rebase with only minor modifications from commit e80720dd9b412a31d1079533323d0b01231926e3
32 lines
1.3 KiB
SQL
32 lines
1.3 KiB
SQL
--parallel queries require big-ish tables so collect them all here
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--so that we need to generate queries only once.
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\ir include/create_single_db.sql
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CREATE TABLE test (i int, j double precision, ts timestamp);
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--has to be big enough to force at least 2 workers below.
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INSERT INTO test SELECT x, x+0.1, _timescaledb_internal.to_timestamp(x*1000) FROM generate_series(1,1000000) AS x;
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SET force_parallel_mode = 'on';
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SET max_parallel_workers_per_gather = 4;
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EXPLAIN (costs off) SELECT first(i, j) FROM "test";
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SELECT first(i, j) FROM "test";
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EXPLAIN (costs off) SELECT last(i, j) FROM "test";
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SELECT last(i, j) FROM "test";
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EXPLAIN (costs off) SELECT time_bucket('1 second', ts) sec, last(i, j) FROM "test" GROUP BY sec ORDER BY sec LIMIT 5;
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SELECT time_bucket('1 second', ts) sec, last(i, j) FROM "test" GROUP BY sec ORDER BY sec LIMIT 5;
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--test variants of histogram
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EXPLAIN (costs off) SELECT histogram(i, 1, 1000000, 2) FROM "test";
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SELECT histogram(i, 1, 1000000, 2) FROM "test";
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EXPLAIN (costs off) SELECT histogram(i, 1,1000001,10) FROM "test";
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SELECT histogram(i, 1, 1000001, 10) FROM "test";
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EXPLAIN (costs off) SELECT histogram(i, 0,100000,5) FROM "test";
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SELECT histogram(i, 0, 100000, 5) FROM "test";
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EXPLAIN (costs off) SELECT histogram(i, 10,100000,5) FROM "test";
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SELECT histogram(i, 10, 100000, 5) FROM "test"; |