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55 lines
2.9 KiB
SQL
55 lines
2.9 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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\o /dev/null
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\ir include/insert_two_partitions.sql
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\o
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SELECT * FROM PUBLIC."two_Partitions";
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EXPLAIN (verbose ON, costs off) SELECT * FROM PUBLIC."two_Partitions";
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\echo "The following queries should NOT scan two_Partitions._hyper_1_1_chunk"
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EXPLAIN (verbose ON, costs off) SELECT * FROM PUBLIC."two_Partitions" WHERE device_id = 'dev2';
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EXPLAIN (verbose ON, costs off) SELECT * FROM PUBLIC."two_Partitions" WHERE device_id = 'dev'||'2';
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EXPLAIN (verbose ON, costs off) SELECT * FROM PUBLIC."two_Partitions" WHERE 'dev'||'2' = device_id;
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--test integer partition key
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CREATE TABLE "int_part"(time timestamp, object_id int, temp float);
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SELECT create_hypertable('"int_part"', 'time', 'object_id', 2);
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INSERT INTO "int_part" VALUES('2017-01-20T09:00:01', 1, 22.5);
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INSERT INTO "int_part" VALUES('2017-01-20T09:00:01', 2, 22.5);
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--check that there are two chunks
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SELECT * FROM test.show_subtables('int_part');
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SELECT * FROM "int_part" WHERE object_id = 1;
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--check that queries with IN/ANY/= work for the "time" column
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SELECT * FROM "int_part" WHERE time IN (NULL);
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SELECT * FROM "int_part" WHERE time = ANY (NULL);
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SELECT * FROM "int_part" WHERE time = NULL;
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--make sure this touches only one partititon
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EXPLAIN (verbose ON, costs off) SELECT * FROM "int_part" WHERE object_id = 1;
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--Need to verify space partitions are currently pruned in this query
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--EXPLAIN (verbose ON, costs off) SELECT * FROM "two_Partitions" WHERE device_id IN ('dev2', 'dev21');
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\echo "The following shows non-aggregated queries with time desc using merge append"
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EXPLAIN (verbose ON, costs off)SELECT * FROM PUBLIC."two_Partitions" ORDER BY "timeCustom" DESC NULLS LAST limit 2;
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--shows that more specific indexes are used if the WHERE clauses "match", uses the series_1 index here.
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EXPLAIN (verbose ON, costs off)SELECT * FROM PUBLIC."two_Partitions" WHERE series_1 IS NOT NULL ORDER BY "timeCustom" DESC NULLS LAST limit 2;
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--here the "match" is implication series_1 > 1 => series_1 IS NOT NULL
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EXPLAIN (verbose ON, costs off)SELECT * FROM PUBLIC."two_Partitions" WHERE series_1 > 1 ORDER BY "timeCustom" DESC NULLS LAST limit 2;
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--note that without time transform things work too
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EXPLAIN (verbose ON, costs off)SELECT "timeCustom" t, min(series_0) FROM PUBLIC."two_Partitions" GROUP BY t ORDER BY t DESC NULLS LAST limit 2;
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--The query should still use the index on timeCustom, even though the GROUP BY/ORDER BY is on the transformed time 't'.
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--However, current query plans show that it does not.
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EXPLAIN (verbose ON, costs off)SELECT "timeCustom"/10 t, min(series_0) FROM PUBLIC."two_Partitions" GROUP BY t ORDER BY t DESC NULLS LAST limit 2;
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EXPLAIN (verbose ON, costs off)SELECT "timeCustom"%10 t, min(series_0) FROM PUBLIC."two_Partitions" GROUP BY t ORDER BY t DESC NULLS LAST limit 2;
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