1 files changed, 100 insertions, 0 deletions
diff --git a/contrib/tsm_system_time/expected/tsm_system_time.out b/contrib/tsm_system_time/expected/tsm_system_time.out
new file mode 100644
index 0000000..ac44f30
--- /dev/null
+++ b/contrib/tsm_system_time/expected/tsm_system_time.out
@@ -0,0 +1,100 @@
+CREATE EXTENSION tsm_system_time;
+CREATE TABLE test_tablesample (id int, name text);
+INSERT INTO test_tablesample SELECT i, repeat(i::text, 1000)
+  FROM generate_series(0, 30) s(i);
+ANALYZE test_tablesample;
+-- It's a bit tricky to test SYSTEM_TIME in a platform-independent way.
+-- We can test the zero-time corner case ...
+SELECT count(*) FROM test_tablesample TABLESAMPLE system_time (0);
+ count 
+-------
+     0
+(1 row)
+
+-- ... and we assume that this will finish before running out of time:
+SELECT count(*) FROM test_tablesample TABLESAMPLE system_time (100000);
+ count 
+-------
+    31
+(1 row)
+
+-- bad parameters should get through planning, but not execution:
+EXPLAIN (COSTS OFF)
+SELECT id FROM test_tablesample TABLESAMPLE system_time (-1);
+                    QUERY PLAN                    
+--------------------------------------------------
+ Sample Scan on test_tablesample
+   Sampling: system_time ('-1'::double precision)
+(2 rows)
+
+SELECT id FROM test_tablesample TABLESAMPLE system_time (-1);
+ERROR:  sample collection time must not be negative
+-- fail, this method is not repeatable:
+SELECT * FROM test_tablesample TABLESAMPLE system_time (10) REPEATABLE (0);
+ERROR:  tablesample method system_time does not support REPEATABLE
+LINE 1: SELECT * FROM test_tablesample TABLESAMPLE system_time (10) ...
+                                                   ^
+-- since it's not repeatable, we expect a Materialize node in these plans:
+EXPLAIN (COSTS OFF)
+SELECT * FROM
+  (VALUES (0),(100000)) v(time),
+  LATERAL (SELECT COUNT(*) FROM test_tablesample
+           TABLESAMPLE system_time (100000)) ss;
+                               QUERY PLAN                               
+------------------------------------------------------------------------
+ Nested Loop
+   ->  Aggregate
+         ->  Materialize
+               ->  Sample Scan on test_tablesample
+                     Sampling: system_time ('100000'::double precision)
+   ->  Values Scan on "*VALUES*"
+(6 rows)
+
+SELECT * FROM
+  (VALUES (0),(100000)) v(time),
+  LATERAL (SELECT COUNT(*) FROM test_tablesample
+           TABLESAMPLE system_time (100000)) ss;
+  time  | count 
+--------+-------
+      0 |    31
+ 100000 |    31
+(2 rows)
+
+EXPLAIN (COSTS OFF)
+SELECT * FROM
+  (VALUES (0),(100000)) v(time),
+  LATERAL (SELECT COUNT(*) FROM test_tablesample
+           TABLESAMPLE system_time (time)) ss;
+                           QUERY PLAN                           
+----------------------------------------------------------------
+ Nested Loop
+   ->  Values Scan on "*VALUES*"
+   ->  Aggregate
+         ->  Materialize
+               ->  Sample Scan on test_tablesample
+                     Sampling: system_time ("*VALUES*".column1)
+(6 rows)
+
+SELECT * FROM
+  (VALUES (0),(100000)) v(time),
+  LATERAL (SELECT COUNT(*) FROM test_tablesample
+           TABLESAMPLE system_time (time)) ss;
+  time  | count 
+--------+-------
+      0 |     0
+ 100000 |    31
+(2 rows)
+
+CREATE VIEW vv AS
+  SELECT * FROM test_tablesample TABLESAMPLE system_time (20);
+EXPLAIN (COSTS OFF) SELECT * FROM vv;
+                    QUERY PLAN                    
+--------------------------------------------------
+ Sample Scan on test_tablesample
+   Sampling: system_time ('20'::double precision)
+(2 rows)
+
+DROP EXTENSION tsm_system_time;  -- fail, view depends on extension
+ERROR:  cannot drop extension tsm_system_time because other objects depend on it
+DETAIL:  view vv depends on function system_time(internal)
+HINT:  Use DROP ... CASCADE to drop the dependent objects too.