Sampling: bernoulli ("*VALUES*".column1)
(8 rows)
-select pct, count(unique1) from
- (values (0),(100)) v(pct),
- lateral (select * from tenk1 tablesample bernoulli (pct)) ss
- group by pct;
- pct | count
------+-------
-(0 rows)
-
-select pct, count(unique1) from
- (values (0),(100)) v(pct),
- lateral (select * from tenk1 tablesample system (pct)) ss
- group by pct;
- pct | count
------+-------
-(0 rows)
-
-- errors
SELECT id FROM test_tablesample TABLESAMPLE FOOBAR (1);
ERROR: tablesample method foobar does not exist
------+--------+------
(0 rows)
+------------------------------------------
+-- from tablesample
+select pct, count(unique1) from
+ (values (0),(100)) v(pct),
+ lateral (select * from tenk1 tablesample bernoulli (pct)) ss
+ group by pct;
+ pct | count
+-----+-------
+ 100 | 10000
+(1 row)
+
+select pct, count(unique1) from
+ (values (0),(100)) v(pct),
+ lateral (select * from tenk1 tablesample system (pct)) ss
+ group by pct;
+ pct | count
+-----+-------
+ 100 | 10000
+(1 row)
+
+------------------------------------------
(values (0),(100)) v(pct),
lateral (select * from tenk1 tablesample bernoulli (pct)) ss
group by pct;
-select pct, count(unique1) from
- (values (0),(100)) v(pct),
- lateral (select * from tenk1 tablesample bernoulli (pct)) ss
- group by pct;
-select pct, count(unique1) from
- (values (0),(100)) v(pct),
- lateral (select * from tenk1 tablesample system (pct)) ss
- group by pct;
-- errors
SELECT id FROM test_tablesample TABLESAMPLE FOOBAR (1);
SELECT *, name(equipment(h.*)) FROM hobbies_r h ORDER BY 1,2,3;
SELECT *, (equipment(CAST((h.*) AS hobbies_r))).name FROM hobbies_r h ORDER BY 1,2,3;
+
+------------------------------------------
+
+-- from tablesample
+
+select pct, count(unique1) from
+ (values (0),(100)) v(pct),
+ lateral (select * from tenk1 tablesample bernoulli (pct)) ss
+ group by pct;
+
+select pct, count(unique1) from
+ (values (0),(100)) v(pct),
+ lateral (select * from tenk1 tablesample system (pct)) ss
+ group by pct;
+
+------------------------------------------