1 files changed, 102 insertions, 0 deletions
diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql
new file mode 100644
index 0000000000..946cb84853
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+++ b/src/test/regress/sql/stats_ext.sql
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+-- Generic extended statistics support
+
+-- Ensure stats are dropped sanely
+CREATE TABLE ab1 (a INTEGER, b INTEGER, c INTEGER);
+CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+DROP STATISTICS ab1_a_b_stats;
+
+CREATE SCHEMA regress_schema_2;
+CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON (a, b) FROM ab1;
+DROP STATISTICS regress_schema_2.ab1_a_b_stats;
+
+-- Ensure statistics are dropped when columns are
+CREATE STATISTICS ab1_b_c_stats ON (b, c) FROM ab1;
+CREATE STATISTICS ab1_a_b_c_stats ON (a, b, c) FROM ab1;
+CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+ALTER TABLE ab1 DROP COLUMN a;
+\d ab1
+DROP TABLE ab1;
+
+-- Ensure things work sanely with SET STATISTICS 0
+CREATE TABLE ab1 (a INTEGER, b INTEGER);
+ALTER TABLE ab1 ALTER a SET STATISTICS 0;
+INSERT INTO ab1 SELECT a, a%23 FROM generate_series(1, 1000) a;
+CREATE STATISTICS ab1_a_b_stats ON (a, b) FROM ab1;
+ANALYZE ab1;
+ALTER TABLE ab1 ALTER a SET STATISTICS -1;
+ANALYZE ab1;
+DROP TABLE ab1;
+
+
+-- n-distinct tests
+CREATE TABLE ndistinct (
+    filler1 TEXT,
+    filler2 NUMERIC,
+    a INT,
+    b INT,
+    filler3 DATE,
+    c INT,
+    d INT
+);
+
+-- unknown column
+CREATE STATISTICS s10 ON (unknown_column) FROM ndistinct;
+
+-- single column
+CREATE STATISTICS s10 ON (a) FROM ndistinct;
+
+-- single column, duplicated
+CREATE STATISTICS s10 ON (a,a) FROM ndistinct;
+
+-- two columns, one duplicated
+CREATE STATISTICS s10 ON (a, a, b) FROM ndistinct;
+
+-- correct command
+CREATE STATISTICS s10 ON (a, b, c) FROM ndistinct;
+
+-- perfectly correlated groups
+INSERT INTO ndistinct (a, b, c, filler1)
+     SELECT i/100, i/100, i/100, cash_words(i::money)
+       FROM generate_series(1,10000) s(i);
+
+ANALYZE ndistinct;
+
+SELECT staenabled, standistinct
+  FROM pg_statistic_ext WHERE starelid = 'ndistinct'::regclass;
+
+EXPLAIN (COSTS off)
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, b;
+
+EXPLAIN (COSTS off)
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, b, c;
+
+EXPLAIN (COSTS off)
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, b, c, d;
+
+TRUNCATE TABLE ndistinct;
+
+-- partially correlated groups
+INSERT INTO ndistinct (a, b, c)
+     SELECT i/50, i/100, i/200 FROM generate_series(1,10000) s(i);
+
+ANALYZE ndistinct;
+
+SELECT staenabled, standistinct
+  FROM pg_statistic_ext WHERE starelid = 'ndistinct'::regclass;
+
+EXPLAIN
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, b;
+
+EXPLAIN
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, b, c;
+
+EXPLAIN
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, b, c, d;
+
+EXPLAIN
+ SELECT COUNT(*) FROM ndistinct GROUP BY b, c, d;
+
+EXPLAIN
+ SELECT COUNT(*) FROM ndistinct GROUP BY a, d;
+
+DROP TABLE ndistinct;