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CREATE EXTENSION tsm_system_rows;
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
INSERT INTO test_tablesample SELECT i, repeat(i::text, 1000) FROM generate_series(0, 30) s(i) ORDER BY i;
ANALYZE test_tablesample;
SELECT count(*) FROM test_tablesample TABLESAMPLE system_rows (1000);
count
-------
31
(1 row)
SELECT id FROM test_tablesample TABLESAMPLE system_rows (8) REPEATABLE (5432);
id
----
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(8 rows)
EXPLAIN SELECT id FROM test_tablesample TABLESAMPLE system_rows (20) REPEATABLE (10);
QUERY PLAN
-----------------------------------------------------------------------------------
Sample Scan (system_rows) on test_tablesample (cost=0.00..80.20 rows=20 width=4)
(1 row)
-- done
DROP TABLE test_tablesample CASCADE;
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