55 lines
1.0 KiB
Plaintext
55 lines
1.0 KiB
Plaintext
CREATE EXTENSION tsm_system_time;
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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_time (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_time (1000) 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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1
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8
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15
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22
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29
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5
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12
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19
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26
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2
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9
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16
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23
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30
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6
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13
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20
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27
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3
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10
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17
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24
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0
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(31 rows)
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EXPLAIN SELECT id FROM test_tablesample TABLESAMPLE system_time (100) REPEATABLE (10);
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QUERY PLAN
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------------------------------------------------------------------------------------
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Sample Scan (system_time) on test_tablesample (cost=0.00..100.25 rows=25 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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