src/test/regress/sql/uao_compaction/full_stats.sql

-- @Description Tests the behavior of full vacuum w.r.t. the pg_class statistics

CREATE TABLE uao_full_stats (a INT, b INT, c CHAR(128)) WITH (appendonly=true) DISTRIBUTED BY (a);
CREATE INDEX uao_full_stats_index ON uao_full_stats(b);
INSERT INTO uao_full_stats SELECT i as a, i as b, 'hello world' as c FROM generate_series(1, 50) AS i;
INSERT INTO uao_full_stats SELECT i as a, i as b, 'hello world' as c FROM generate_series(51, 100) AS i;
ANALYZE uao_full_stats;

-- ensure that the scan go through the index
SET enable_seqscan=false;
SELECT relname, reltuples FROM pg_class WHERE relname = 'uao_full_stats';
SELECT relname, reltuples FROM pg_class WHERE relname = 'uao_full_stats_index';
DELETE FROM uao_full_stats WHERE a < 16;
VACUUM FULL uao_full_stats;
SELECT relname, reltuples FROM pg_class WHERE relname = 'uao_full_stats';
-- New strategy of VACUUM AO/CO was introduced by PR #13255 for performance enhancement.
-- Index dead tuples will not always be cleaned up completely after VACUUM, resulting
-- index stats pg_class->reltuples will not always be accurate. So ignore the stats check
-- for reltuples to coordinate with the new behavior.
-- start_ignore
SELECT relname, reltuples FROM pg_class WHERE relname = 'uao_full_stats_index';
-- end_ignore