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src/test/regress/expected/bitmapops.out
48 строк
2 KB
Melanie Plageman
Fix bitmapheapscan incorrect recheck of NULL tuples
24 мар 2025, 23:40
24 мар 2025, 23:40
aea916f
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-- Test bitmap AND and OR -- Generate enough data that we can test the lossy bitmaps. -- There's 55 tuples per page in the table. 53 is just -- below 55, so that an index scan with qual a = constant -- will return at least one hit per page. 59 is just above -- 55, so that an index scan with qual b = constant will return -- hits on most but not all pages. 53 and 59 are prime, so that -- there's a maximum number of a,b combinations in the table. -- That allows us to test all the different combinations of -- lossy and non-lossy pages with the minimum amount of data CREATE TABLE bmscantest (a int, b int, t text) WITH (autovacuum_enabled = false); INSERT INTO bmscantest SELECT (r%53), (r%59), 'foooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo' FROM generate_series(1,70000) r; CREATE INDEX i_bmtest_a ON bmscantest(a); CREATE INDEX i_bmtest_b ON bmscantest(b); -- We want to use bitmapscans. With default settings, the planner currently -- chooses a bitmap scan for the queries below anyway, but let's make sure. set enable_indexscan=false; set enable_seqscan=false; -- Lower work_mem to trigger use of lossy bitmaps set work_mem = 64; -- Test bitmap-and without the skip fetch optimization. SELECT count(*) FROM bmscantest WHERE a = 1 AND b = 1; count ------- 23 (1 row) -- Test that we return correct results when using the skip fetch optimization -- VACUUM FREEZE will set all the pages in the relation all-visible, enabling -- the optimization. VACUUM (FREEZE) bmscantest; SELECT count(*) FROM bmscantest WHERE a = 1 AND b = 1; count ------- 23 (1 row) -- Test bitmap-or. SELECT count(*) FROM bmscantest WHERE a = 1 OR b = 1; count ------- 2485 (1 row) -- clean up DROP TABLE bmscantest;