postgresql/src/test/regress/expected/tablesample.out

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, 200) FROM generate_series(0, 9) s(i) ORDER BY i;
SELECT t.id FROM test_tablesample AS t TABLESAMPLE SYSTEM (50) REPEATABLE (10);
 id 
----
  0
  1
  2
  3
  4
  5
  9
(7 rows)

SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (100.0/11) REPEATABLE (9999);
 id 
----
  6
  7
  8
(3 rows)

SELECT count(*) FROM test_tablesample TABLESAMPLE SYSTEM (100);
 count 
-------
    10
(1 row)

SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (50) REPEATABLE (100);
 id 
----
  0
  1
  2
  6
  7
  8
  9
(7 rows)

SELECT id FROM test_tablesample TABLESAMPLE BERNOULLI (50) REPEATABLE (100);
 id 
----
  0
  1
  3
  4
  5
(5 rows)

SELECT id FROM test_tablesample TABLESAMPLE BERNOULLI (5.5) REPEATABLE (1);
 id 
----
  0
  5
(2 rows)

CREATE VIEW test_tablesample_v1 AS SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (10*2) REPEATABLE (2);
CREATE VIEW test_tablesample_v2 AS SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (99);
SELECT pg_get_viewdef('test_tablesample_v1'::regclass);
                                 pg_get_viewdef                                 
--------------------------------------------------------------------------------
  SELECT test_tablesample.id                                                   +
    FROM test_tablesample TABLESAMPLE system (((10 * 2))::real) REPEATABLE (2);
(1 row)

SELECT pg_get_viewdef('test_tablesample_v2'::regclass);
                      pg_get_viewdef                       
-----------------------------------------------------------
  SELECT test_tablesample.id                              +
    FROM test_tablesample TABLESAMPLE system ((99)::real);
(1 row)

BEGIN;
DECLARE tablesample_cur CURSOR FOR SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (50) REPEATABLE (100);
FETCH FIRST FROM tablesample_cur;
 id 
----
  0
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  1
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  2
(1 row)

SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (50) REPEATABLE (10);
 id 
----
  0
  1
  2
  3
  4
  5
  9
(7 rows)

FETCH NEXT FROM tablesample_cur;
 id 
----
  6
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  7
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  8
(1 row)

FETCH FIRST FROM tablesample_cur;
 id 
----
  0
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  1
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  2
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  6
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  7
(1 row)

FETCH NEXT FROM tablesample_cur;
 id 
----
  8
(1 row)

CLOSE tablesample_cur;
END;
EXPLAIN SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (50) REPEATABLE (10);
                                  QUERY PLAN                                   
-------------------------------------------------------------------------------
 Sample Scan (system) on test_tablesample  (cost=0.00..26.35 rows=635 width=4)
(1 row)

EXPLAIN SELECT * FROM test_tablesample_v1;
                                  QUERY PLAN                                   
-------------------------------------------------------------------------------
 Sample Scan (system) on test_tablesample  (cost=0.00..10.54 rows=254 width=4)
(1 row)

-- errors
SELECT id FROM test_tablesample TABLESAMPLE FOOBAR (1);
ERROR:  tablesample method "foobar" does not exist
LINE 1: SELECT id FROM test_tablesample TABLESAMPLE FOOBAR (1);
                       ^
SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (50) REPEATABLE (NULL);
ERROR:  REPEATABLE clause must be NOT NULL numeric value
LINE 1: ... test_tablesample TABLESAMPLE SYSTEM (50) REPEATABLE (NULL);
                                                                 ^
SELECT id FROM test_tablesample TABLESAMPLE BERNOULLI (-1);
ERROR:  invalid sample size
HINT:  Sample size must be numeric value between 0 and 100 (inclusive).
SELECT id FROM test_tablesample TABLESAMPLE BERNOULLI (200);
ERROR:  invalid sample size
HINT:  Sample size must be numeric value between 0 and 100 (inclusive).
SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (-1);
ERROR:  invalid sample size
HINT:  Sample size must be numeric value between 0 and 100 (inclusive).
SELECT id FROM test_tablesample TABLESAMPLE SYSTEM (200);
ERROR:  invalid sample size
HINT:  Sample size must be numeric value between 0 and 100 (inclusive).
SELECT id FROM test_tablesample_v1 TABLESAMPLE BERNOULLI (1);
ERROR:  TABLESAMPLE clause can only be used on tables and materialized views
LINE 1: SELECT id FROM test_tablesample_v1 TABLESAMPLE BERNOULLI (1)...
                       ^
INSERT INTO test_tablesample_v1 VALUES(1);
ERROR:  cannot insert into view "test_tablesample_v1"
DETAIL:  Views containing TABLESAMPLE are not automatically updatable.
HINT:  To enable inserting into the view, provide an INSTEAD OF INSERT trigger or an unconditional ON INSERT DO INSTEAD rule.
WITH query_select AS (SELECT * FROM test_tablesample)
SELECT * FROM query_select TABLESAMPLE BERNOULLI (5.5) REPEATABLE (1);
ERROR:  TABLESAMPLE clause can only be used on tables and materialized views
LINE 2: SELECT * FROM query_select TABLESAMPLE BERNOULLI (5.5) REPEA...
                      ^
SELECT q.* FROM (SELECT * FROM test_tablesample) as q TABLESAMPLE BERNOULLI (5);
ERROR:  syntax error at or near "TABLESAMPLE"
LINE 1: ...CT q.* FROM (SELECT * FROM test_tablesample) as q TABLESAMPL...
                                                             ^
-- catalog sanity
SELECT *
FROM pg_tablesample_method
WHERE tsminit IS NULL
   OR tsmseqscan IS NULL
   OR tsmpagemode IS NULL
   OR tsmnextblock IS NULL
   OR tsmnexttuple IS NULL
   OR tsmend IS NULL
   OR tsmreset IS NULL
   OR tsmcost IS NULL;
 tsmname | tsmseqscan | tsmpagemode | tsminit | tsmnextblock | tsmnexttuple | tsmexaminetuple | tsmend | tsmreset | tsmcost 
---------+------------+-------------+---------+--------------+--------------+-----------------+--------+----------+---------
(0 rows)

-- done
DROP TABLE test_tablesample CASCADE;
NOTICE:  drop cascades to 2 other objects
DETAIL:  drop cascades to view test_tablesample_v1
drop cascades to view test_tablesample_v2