-- Test that partial indexes have all pages, including empty ones. CREATETABLE test2 (a int); INSERTINTO test2 SELECT i FROM generate_series(1,1000) s(i);
-- No rows match the index predicate, make sure the index has the right number -- of ranges (same as number of page ranges). CREATEINDEXON test2 USING brin (a) WITH (pages_per_range=1) WHERE (a ISNULL);
ANALYZE test2;
-- Does the index have one summary of the relation? SELECT (COUNT(*) = (SELECT relpages FROM pg_class WHERE relname = 'test2')) AS ranges_do_match FROM generate_series((SELECT (lastrevmappage + 1) FROM brin_metapage_info(get_raw_page('test2_a_idx', 0))),
(SELECT (relpages - 1) FROM pg_class WHERE relname = 'test2_a_idx')) AS pages(p),
LATERAL brin_page_items(get_raw_page('test2_a_idx', p), 'test2_a_idx') AS items;
DROPTABLE test1; DROPTABLE test2;
-- Test that parallel index build produces the same BRIN index as serial build. CREATETABLE brin_parallel_test (a int, b text, c bigint) WITH (fillfactor=40);
-- Generate a table with a mix of NULLs and non-NULL values (and data suitable -- for the different opclasses we build later). INSERTINTO brin_parallel_test SELECT (CASEWHEN (mod(i,231) = 0) OR (i BETWEEN3500AND4000) THENNULLELSE i END),
(CASEWHEN (mod(i,233) = 0) OR (i BETWEEN3750AND4250) THENNULLELSE encode(sha256(i::text::bytea), 'hex') END),
(CASEWHEN (mod(i,233) = 0) OR (i BETWEEN3850AND4500) THENNULLELSE (i/100) + mod(i,8) END) FROM generate_series(1,5000) S(i);
-- Build an index with different opclasses - minmax, bloom and minmax-multi. -- -- For minmax and opclass this is simple, but for minmax-multi we need to be -- careful, because the result depends on the order in which values are added -- to the summary, which in turn affects how are values merged etc. The order -- of merging results from workers has similar effect. All those summaries -- should produce correct query results, but it means we can't compare them -- using equality (which is what EXCEPT does). To work around this issue, we -- generated the data to only have very small number of distinct values per -- range, so that no merging is needed. This makes the results deterministic.
-- build index without parallelism SET max_parallel_maintenance_workers = 0; CREATEINDEX brin_test_serial_idx ON brin_parallel_test USING brin (a int4_minmax_ops, a int4_bloom_ops, b, c int8_minmax_multi_ops) WITH (pages_per_range=7) WHERENOT (a BETWEEN1000and1500);
-- build index using parallelism -- -- Set a couple parameters to force parallel build for small table. There's a -- requirement for table size, so disable that. Also, plan_create_index_workers -- assumes each worker will use work_mem=32MB for sorting (which works for btree, -- but not really for BRIN), so we set maintenance_work_mem for 4 workers. SET min_parallel_table_scan_size = 0; SET max_parallel_maintenance_workers = 4; SET maintenance_work_mem = '128MB'; CREATEINDEX brin_test_parallel_idx ON brin_parallel_test USING brin (a int4_minmax_ops, a int4_bloom_ops, b, c int8_minmax_multi_ops) WITH (pages_per_range=7) WHERENOT (a BETWEEN1000and1500);
SELECT relname, relpages FROM pg_class WHERE relname IN ('brin_test_serial_idx', 'brin_test_parallel_idx') ORDERBY relname;
-- Check that (A except B) and (B except A) is empty, which means the indexes -- are the same.
SELECT * FROM brin_page_items(get_raw_page('brin_test_parallel_idx', 2), 'brin_test_parallel_idx')
EXCEPT SELECT * FROM brin_page_items(get_raw_page('brin_test_serial_idx', 2), 'brin_test_serial_idx');
SELECT * FROM brin_page_items(get_raw_page('brin_test_serial_idx', 2), 'brin_test_serial_idx')
EXCEPT SELECT * FROM brin_page_items(get_raw_page('brin_test_parallel_idx', 2), 'brin_test_parallel_idx');
DROPINDEX brin_test_parallel_idx;
-- force parallel build, but don't allow starting parallel workers to force -- fallback to serial build, and repeat the checks
SET max_parallel_workers = 0; CREATEINDEX brin_test_parallel_idx ON brin_parallel_test USING brin (a int4_minmax_ops, a int4_bloom_ops, b, c int8_minmax_multi_ops) WITH (pages_per_range=7) WHERENOT (a BETWEEN1000and1500);
SELECT relname, relpages FROM pg_class WHERE relname IN ('brin_test_serial_idx', 'brin_test_parallel_idx') ORDERBY relname;
SELECT * FROM brin_page_items(get_raw_page('brin_test_parallel_idx', 2), 'brin_test_parallel_idx')
EXCEPT SELECT * FROM brin_page_items(get_raw_page('brin_test_serial_idx', 2), 'brin_test_serial_idx');
SELECT * FROM brin_page_items(get_raw_page('brin_test_serial_idx', 2), 'brin_test_serial_idx')
EXCEPT SELECT * FROM brin_page_items(get_raw_page('brin_test_parallel_idx', 2), 'brin_test_parallel_idx');
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