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32 lines
946 B
Plaintext
32 lines
946 B
Plaintext
CREATE EXTENSION tsm_system_rows;
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CREATE TABLE test_tablesample (id int, name text) WITH (fillfactor=10); -- force smaller pages so we don't have to load too much data to get multiple pages
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INSERT INTO test_tablesample SELECT i, repeat(i::text, 1000) FROM generate_series(0, 30) s(i) ORDER BY i;
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ANALYZE test_tablesample;
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SELECT count(*) FROM test_tablesample TABLESAMPLE system_rows (1000);
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count
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-------
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31
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(1 row)
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SELECT id FROM test_tablesample TABLESAMPLE system_rows (8) REPEATABLE (5432);
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id
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----
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7
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14
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21
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28
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4
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11
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18
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25
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(8 rows)
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EXPLAIN SELECT id FROM test_tablesample TABLESAMPLE system_rows (20) REPEATABLE (10);
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QUERY PLAN
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-----------------------------------------------------------------------------------
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Sample Scan (system_rows) on test_tablesample (cost=0.00..80.20 rows=20 width=4)
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(1 row)
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-- done
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DROP TABLE test_tablesample CASCADE;
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