ydb/yql/essentials/tests/postgresql/original/cases/union.out

--
-- UNION (also INTERSECT, EXCEPT)
--
-- Simple UNION constructs
SELECT 1 AS two UNION SELECT 2 ORDER BY 1;
 two 
-----
   1
   2
(2 rows)

SELECT 1 AS one UNION SELECT 1 ORDER BY 1;
 one 
-----
   1
(1 row)

SELECT 1 AS two UNION ALL SELECT 2;
 two 
-----
   1
   2
(2 rows)

SELECT 1 AS two UNION ALL SELECT 1;
 two 
-----
   1
   1
(2 rows)

SELECT 1 AS three UNION SELECT 2 UNION SELECT 3 ORDER BY 1;
 three 
-------
     1
     2
     3
(3 rows)

SELECT 1 AS two UNION SELECT 2 UNION SELECT 2 ORDER BY 1;
 two 
-----
   1
   2
(2 rows)

SELECT 1 AS three UNION SELECT 2 UNION ALL SELECT 2 ORDER BY 1;
 three 
-------
     1
     2
     2
(3 rows)

SELECT 1.1 AS two UNION SELECT 2.2 ORDER BY 1;
 two 
-----
 1.1
 2.2
(2 rows)

-- Mixed types
SELECT 1.1 AS two UNION SELECT 2 ORDER BY 1;
 two 
-----
 1.1
   2
(2 rows)

SELECT 1 AS two UNION SELECT 2.2 ORDER BY 1;
 two 
-----
   1
 2.2
(2 rows)

SELECT 1 AS one UNION SELECT 1.0::float8 ORDER BY 1;
 one 
-----
   1
(1 row)

SELECT 1.1 AS two UNION ALL SELECT 2 ORDER BY 1;
 two 
-----
 1.1
   2
(2 rows)

SELECT 1.0::float8 AS two UNION ALL SELECT 1 ORDER BY 1;
 two 
-----
   1
   1
(2 rows)

SELECT 1.1 AS three UNION SELECT 2 UNION SELECT 3 ORDER BY 1;
 three 
-------
   1.1
     2
     3
(3 rows)

SELECT 1.1::float8 AS two UNION SELECT 2 UNION SELECT 2.0::float8 ORDER BY 1;
 two 
-----
 1.1
   2
(2 rows)

SELECT 1.1 AS three UNION SELECT 2 UNION ALL SELECT 2 ORDER BY 1;
 three 
-------
   1.1
     2
     2
(3 rows)

SELECT 1.1 AS two UNION (SELECT 2 UNION ALL SELECT 2) ORDER BY 1;
 two 
-----
 1.1
   2
(2 rows)

--
-- Try testing from tables...
--
SELECT f1 AS five FROM FLOAT8_TBL
UNION
SELECT f1 FROM FLOAT8_TBL
ORDER BY 1;
         five          
-----------------------
 -1.2345678901234e+200
               -1004.3
                -34.84
 -1.2345678901234e-200
                     0
(5 rows)

SELECT f1 AS ten FROM FLOAT8_TBL
UNION ALL
SELECT f1 FROM FLOAT8_TBL;
          ten          
-----------------------
                     0
                -34.84
               -1004.3
 -1.2345678901234e+200
 -1.2345678901234e-200
                     0
                -34.84
               -1004.3
 -1.2345678901234e+200
 -1.2345678901234e-200
(10 rows)

SELECT f1 AS nine FROM FLOAT8_TBL
UNION
SELECT f1 FROM INT4_TBL
ORDER BY 1;
         nine          
-----------------------
 -1.2345678901234e+200
           -2147483647
               -123456
               -1004.3
                -34.84
 -1.2345678901234e-200
                     0
                123456
            2147483647
(9 rows)

SELECT f1 AS ten FROM FLOAT8_TBL
UNION ALL
SELECT f1 FROM INT4_TBL;
          ten          
-----------------------
                     0
                -34.84
               -1004.3
 -1.2345678901234e+200
 -1.2345678901234e-200
                     0
                123456
               -123456
            2147483647
           -2147483647
(10 rows)

SELECT f1 AS five FROM FLOAT8_TBL
  WHERE f1 BETWEEN -1e6 AND 1e6
UNION
SELECT f1 FROM INT4_TBL
  WHERE f1 BETWEEN 0 AND 1000000
ORDER BY 1;
         five          
-----------------------
               -1004.3
                -34.84
 -1.2345678901234e-200
                     0
                123456
(5 rows)

SELECT CAST(f1 AS char(4)) AS three FROM VARCHAR_TBL
UNION
SELECT f1 FROM CHAR_TBL
ORDER BY 1;
 three 
-------
 a   
 ab  
 abcd
(3 rows)

SELECT f1 AS three FROM VARCHAR_TBL
UNION
SELECT CAST(f1 AS varchar) FROM CHAR_TBL
ORDER BY 1;
 three 
-------
 a
 ab
 abcd
(3 rows)

SELECT f1 AS eight FROM VARCHAR_TBL
UNION ALL
SELECT f1 FROM CHAR_TBL;
 eight 
-------
 a
 ab
 abcd
 abcd
 a
 ab
 abcd
 abcd
(8 rows)

SELECT f1 AS five FROM TEXT_TBL
UNION
SELECT f1 FROM VARCHAR_TBL
UNION
SELECT TRIM(TRAILING FROM f1) FROM CHAR_TBL
ORDER BY 1;
       five        
-------------------
 a
 ab
 abcd
 doh!
 hi de ho neighbor
(5 rows)

--
-- INTERSECT and EXCEPT
--
SELECT q2 FROM int8_tbl INTERSECT SELECT q1 FROM int8_tbl ORDER BY 1;
        q2        
------------------
              123
 4567890123456789
(2 rows)

SELECT q2 FROM int8_tbl INTERSECT ALL SELECT q1 FROM int8_tbl ORDER BY 1;
        q2        
------------------
              123
 4567890123456789
 4567890123456789
(3 rows)

SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
        q2         
-------------------
 -4567890123456789
               456
(2 rows)

SELECT q2 FROM int8_tbl EXCEPT ALL SELECT q1 FROM int8_tbl ORDER BY 1;
        q2         
-------------------
 -4567890123456789
               456
(2 rows)

SELECT q2 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q1 FROM int8_tbl ORDER BY 1;
        q2         
-------------------
 -4567890123456789
               456
  4567890123456789
(3 rows)

SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl ORDER BY 1;
 q1 
----
(0 rows)

SELECT q1 FROM int8_tbl EXCEPT ALL SELECT q2 FROM int8_tbl ORDER BY 1;
        q1        
------------------
              123
 4567890123456789
(2 rows)

SELECT q1 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q2 FROM int8_tbl ORDER BY 1;
        q1        
------------------
              123
 4567890123456789
 4567890123456789
(3 rows)

SELECT q1 FROM int8_tbl EXCEPT ALL SELECT q1 FROM int8_tbl FOR NO KEY UPDATE;
ERROR:  FOR NO KEY UPDATE is not allowed with UNION/INTERSECT/EXCEPT
-- nested cases
(SELECT 1,2,3 UNION SELECT 4,5,6) INTERSECT SELECT 4,5,6;
 ?column? | ?column? | ?column? 
----------+----------+----------
        4 |        5 |        6
(1 row)

(SELECT 1,2,3 UNION SELECT 4,5,6 ORDER BY 1,2) INTERSECT SELECT 4,5,6;
 ?column? | ?column? | ?column? 
----------+----------+----------
        4 |        5 |        6
(1 row)

(SELECT 1,2,3 UNION SELECT 4,5,6) EXCEPT SELECT 4,5,6;
 ?column? | ?column? | ?column? 
----------+----------+----------
        1 |        2 |        3
(1 row)

(SELECT 1,2,3 UNION SELECT 4,5,6 ORDER BY 1,2) EXCEPT SELECT 4,5,6;
 ?column? | ?column? | ?column? 
----------+----------+----------
        1 |        2 |        3
(1 row)

-- exercise both hashed and sorted implementations of UNION/INTERSECT/EXCEPT
set enable_hashagg to on;
explain (costs off)
select count(*) from
  ( select unique1 from tenk1 union select fivethous from tenk1 ) ss;
                           QUERY PLAN                           
----------------------------------------------------------------
 Aggregate
   ->  HashAggregate
         Group Key: tenk1.unique1
         ->  Append
               ->  Index Only Scan using tenk1_unique1 on tenk1
               ->  Seq Scan on tenk1 tenk1_1
(6 rows)

select count(*) from
  ( select unique1 from tenk1 union select fivethous from tenk1 ) ss;
 count 
-------
 10000
(1 row)

explain (costs off)
select count(*) from
  ( select unique1 from tenk1 intersect select fivethous from tenk1 ) ss;
                                     QUERY PLAN                                     
------------------------------------------------------------------------------------
 Aggregate
   ->  Subquery Scan on ss
         ->  HashSetOp Intersect
               ->  Append
                     ->  Subquery Scan on "*SELECT* 2"
                           ->  Seq Scan on tenk1
                     ->  Subquery Scan on "*SELECT* 1"
                           ->  Index Only Scan using tenk1_unique1 on tenk1 tenk1_1
(8 rows)

select count(*) from
  ( select unique1 from tenk1 intersect select fivethous from tenk1 ) ss;
 count 
-------
  5000
(1 row)

explain (costs off)
select unique1 from tenk1 except select unique2 from tenk1 where unique2 != 10;
                               QUERY PLAN                               
------------------------------------------------------------------------
 HashSetOp Except
   ->  Append
         ->  Subquery Scan on "*SELECT* 1"
               ->  Index Only Scan using tenk1_unique1 on tenk1
         ->  Subquery Scan on "*SELECT* 2"
               ->  Index Only Scan using tenk1_unique2 on tenk1 tenk1_1
                     Filter: (unique2 <> 10)
(7 rows)

select unique1 from tenk1 except select unique2 from tenk1 where unique2 != 10;
 unique1 
---------
      10
(1 row)

set enable_hashagg to off;
explain (costs off)
select count(*) from
  ( select unique1 from tenk1 union select fivethous from tenk1 ) ss;
                              QUERY PLAN                              
----------------------------------------------------------------------
 Aggregate
   ->  Unique
         ->  Sort
               Sort Key: tenk1.unique1
               ->  Append
                     ->  Index Only Scan using tenk1_unique1 on tenk1
                     ->  Seq Scan on tenk1 tenk1_1
(7 rows)

select count(*) from
  ( select unique1 from tenk1 union select fivethous from tenk1 ) ss;
 count 
-------
 10000
(1 row)

explain (costs off)
select count(*) from
  ( select unique1 from tenk1 intersect select fivethous from tenk1 ) ss;
                                        QUERY PLAN                                        
------------------------------------------------------------------------------------------
 Aggregate
   ->  Subquery Scan on ss
         ->  SetOp Intersect
               ->  Sort
                     Sort Key: "*SELECT* 2".fivethous
                     ->  Append
                           ->  Subquery Scan on "*SELECT* 2"
                                 ->  Seq Scan on tenk1
                           ->  Subquery Scan on "*SELECT* 1"
                                 ->  Index Only Scan using tenk1_unique1 on tenk1 tenk1_1
(10 rows)

select count(*) from
  ( select unique1 from tenk1 intersect select fivethous from tenk1 ) ss;
 count 
-------
  5000
(1 row)

explain (costs off)
select unique1 from tenk1 except select unique2 from tenk1 where unique2 != 10;
                                  QUERY PLAN                                  
------------------------------------------------------------------------------
 SetOp Except
   ->  Sort
         Sort Key: "*SELECT* 1".unique1
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Index Only Scan using tenk1_unique1 on tenk1
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Index Only Scan using tenk1_unique2 on tenk1 tenk1_1
                           Filter: (unique2 <> 10)
(9 rows)

select unique1 from tenk1 except select unique2 from tenk1 where unique2 != 10;
 unique1 
---------
      10
(1 row)

reset enable_hashagg;
-- non-hashable type
set enable_hashagg to on;
explain (costs off)
select x from (values (100::money), (200::money)) _(x) union select x from (values (100::money), (300::money)) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

set enable_hashagg to off;
explain (costs off)
select x from (values (100::money), (200::money)) _(x) union select x from (values (100::money), (300::money)) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

reset enable_hashagg;
-- arrays
set enable_hashagg to on;
explain (costs off)
select x from (values (array[1, 2]), (array[1, 3])) _(x) union select x from (values (array[1, 2]), (array[1, 4])) _(x);
               QUERY PLAN                
-----------------------------------------
 HashAggregate
   Group Key: "*VALUES*".column1
   ->  Append
         ->  Values Scan on "*VALUES*"
         ->  Values Scan on "*VALUES*_1"
(5 rows)

select x from (values (array[1, 2]), (array[1, 3])) _(x) union select x from (values (array[1, 2]), (array[1, 4])) _(x);
   x   
-------
 {1,4}
 {1,2}
 {1,3}
(3 rows)

explain (costs off)
select x from (values (array[1, 2]), (array[1, 3])) _(x) intersect select x from (values (array[1, 2]), (array[1, 4])) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 HashSetOp Intersect
   ->  Append
         ->  Subquery Scan on "*SELECT* 1"
               ->  Values Scan on "*VALUES*"
         ->  Subquery Scan on "*SELECT* 2"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (array[1, 2]), (array[1, 3])) _(x) intersect select x from (values (array[1, 2]), (array[1, 4])) _(x);
   x   
-------
 {1,2}
(1 row)

explain (costs off)
select x from (values (array[1, 2]), (array[1, 3])) _(x) except select x from (values (array[1, 2]), (array[1, 4])) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 HashSetOp Except
   ->  Append
         ->  Subquery Scan on "*SELECT* 1"
               ->  Values Scan on "*VALUES*"
         ->  Subquery Scan on "*SELECT* 2"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (array[1, 2]), (array[1, 3])) _(x) except select x from (values (array[1, 2]), (array[1, 4])) _(x);
   x   
-------
 {1,3}
(1 row)

-- non-hashable type
explain (costs off)
select x from (values (array[100::money]), (array[200::money])) _(x) union select x from (values (array[100::money]), (array[300::money])) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (array[100::money]), (array[200::money])) _(x) union select x from (values (array[100::money]), (array[300::money])) _(x);
     x     
-----------
 {$100.00}
 {$200.00}
 {$300.00}
(3 rows)

set enable_hashagg to off;
explain (costs off)
select x from (values (array[1, 2]), (array[1, 3])) _(x) union select x from (values (array[1, 2]), (array[1, 4])) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (array[1, 2]), (array[1, 3])) _(x) union select x from (values (array[1, 2]), (array[1, 4])) _(x);
   x   
-------
 {1,2}
 {1,3}
 {1,4}
(3 rows)

explain (costs off)
select x from (values (array[1, 2]), (array[1, 3])) _(x) intersect select x from (values (array[1, 2]), (array[1, 4])) _(x);
                     QUERY PLAN                      
-----------------------------------------------------
 SetOp Intersect
   ->  Sort
         Sort Key: "*SELECT* 1".x
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Values Scan on "*VALUES*"
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Values Scan on "*VALUES*_1"
(8 rows)

select x from (values (array[1, 2]), (array[1, 3])) _(x) intersect select x from (values (array[1, 2]), (array[1, 4])) _(x);
   x   
-------
 {1,2}
(1 row)

explain (costs off)
select x from (values (array[1, 2]), (array[1, 3])) _(x) except select x from (values (array[1, 2]), (array[1, 4])) _(x);
                     QUERY PLAN                      
-----------------------------------------------------
 SetOp Except
   ->  Sort
         Sort Key: "*SELECT* 1".x
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Values Scan on "*VALUES*"
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Values Scan on "*VALUES*_1"
(8 rows)

select x from (values (array[1, 2]), (array[1, 3])) _(x) except select x from (values (array[1, 2]), (array[1, 4])) _(x);
   x   
-------
 {1,3}
(1 row)

reset enable_hashagg;
-- records
set enable_hashagg to on;
explain (costs off)
select x from (values (row(1, 2)), (row(1, 3))) _(x) union select x from (values (row(1, 2)), (row(1, 4))) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (row(1, 2)), (row(1, 3))) _(x) union select x from (values (row(1, 2)), (row(1, 4))) _(x);
   x   
-------
 (1,2)
 (1,3)
 (1,4)
(3 rows)

explain (costs off)
select x from (values (row(1, 2)), (row(1, 3))) _(x) intersect select x from (values (row(1, 2)), (row(1, 4))) _(x);
                     QUERY PLAN                      
-----------------------------------------------------
 SetOp Intersect
   ->  Sort
         Sort Key: "*SELECT* 1".x
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Values Scan on "*VALUES*"
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Values Scan on "*VALUES*_1"
(8 rows)

select x from (values (row(1, 2)), (row(1, 3))) _(x) intersect select x from (values (row(1, 2)), (row(1, 4))) _(x);
   x   
-------
 (1,2)
(1 row)

explain (costs off)
select x from (values (row(1, 2)), (row(1, 3))) _(x) except select x from (values (row(1, 2)), (row(1, 4))) _(x);
                     QUERY PLAN                      
-----------------------------------------------------
 SetOp Except
   ->  Sort
         Sort Key: "*SELECT* 1".x
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Values Scan on "*VALUES*"
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Values Scan on "*VALUES*_1"
(8 rows)

select x from (values (row(1, 2)), (row(1, 3))) _(x) except select x from (values (row(1, 2)), (row(1, 4))) _(x);
   x   
-------
 (1,3)
(1 row)

-- non-hashable type
-- With an anonymous row type, the typcache does not report that the
-- type is hashable.  (Otherwise, this would fail at execution time.)
explain (costs off)
select x from (values (row(100::money)), (row(200::money))) _(x) union select x from (values (row(100::money)), (row(300::money))) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (row(100::money)), (row(200::money))) _(x) union select x from (values (row(100::money)), (row(300::money))) _(x);
     x     
-----------
 ($100.00)
 ($200.00)
 ($300.00)
(3 rows)

-- With a defined row type, the typcache can inspect the type's fields
-- for hashability.
create type ct1 as (f1 money);
explain (costs off)
select x from (values (row(100::money)::ct1), (row(200::money)::ct1)) _(x) union select x from (values (row(100::money)::ct1), (row(300::money)::ct1)) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (row(100::money)::ct1), (row(200::money)::ct1)) _(x) union select x from (values (row(100::money)::ct1), (row(300::money)::ct1)) _(x);
     x     
-----------
 ($100.00)
 ($200.00)
 ($300.00)
(3 rows)

drop type ct1;
set enable_hashagg to off;
explain (costs off)
select x from (values (row(1, 2)), (row(1, 3))) _(x) union select x from (values (row(1, 2)), (row(1, 4))) _(x);
                  QUERY PLAN                   
-----------------------------------------------
 Unique
   ->  Sort
         Sort Key: "*VALUES*".column1
         ->  Append
               ->  Values Scan on "*VALUES*"
               ->  Values Scan on "*VALUES*_1"
(6 rows)

select x from (values (row(1, 2)), (row(1, 3))) _(x) union select x from (values (row(1, 2)), (row(1, 4))) _(x);
   x   
-------
 (1,2)
 (1,3)
 (1,4)
(3 rows)

explain (costs off)
select x from (values (row(1, 2)), (row(1, 3))) _(x) intersect select x from (values (row(1, 2)), (row(1, 4))) _(x);
                     QUERY PLAN                      
-----------------------------------------------------
 SetOp Intersect
   ->  Sort
         Sort Key: "*SELECT* 1".x
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Values Scan on "*VALUES*"
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Values Scan on "*VALUES*_1"
(8 rows)

select x from (values (row(1, 2)), (row(1, 3))) _(x) intersect select x from (values (row(1, 2)), (row(1, 4))) _(x);
   x   
-------
 (1,2)
(1 row)

explain (costs off)
select x from (values (row(1, 2)), (row(1, 3))) _(x) except select x from (values (row(1, 2)), (row(1, 4))) _(x);
                     QUERY PLAN                      
-----------------------------------------------------
 SetOp Except
   ->  Sort
         Sort Key: "*SELECT* 1".x
         ->  Append
               ->  Subquery Scan on "*SELECT* 1"
                     ->  Values Scan on "*VALUES*"
               ->  Subquery Scan on "*SELECT* 2"
                     ->  Values Scan on "*VALUES*_1"
(8 rows)

select x from (values (row(1, 2)), (row(1, 3))) _(x) except select x from (values (row(1, 2)), (row(1, 4))) _(x);
   x   
-------
 (1,3)
(1 row)

reset enable_hashagg;
--
-- Mixed types
--
SELECT f1 FROM float8_tbl INTERSECT SELECT f1 FROM int4_tbl ORDER BY 1;
 f1 
----
  0
(1 row)

SELECT f1 FROM float8_tbl EXCEPT SELECT f1 FROM int4_tbl ORDER BY 1;
          f1           
-----------------------
 -1.2345678901234e+200
               -1004.3
                -34.84
 -1.2345678901234e-200
(4 rows)

--
-- Operator precedence and (((((extra))))) parentheses
--
SELECT q1 FROM int8_tbl INTERSECT SELECT q2 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl  ORDER BY 1;
        q1         
-------------------
 -4567890123456789
               123
               123
               456
  4567890123456789
  4567890123456789
  4567890123456789
(7 rows)

SELECT q1 FROM int8_tbl INTERSECT (((SELECT q2 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl))) ORDER BY 1;
        q1        
------------------
              123
 4567890123456789
(2 rows)

(((SELECT q1 FROM int8_tbl INTERSECT SELECT q2 FROM int8_tbl ORDER BY 1))) UNION ALL SELECT q2 FROM int8_tbl;
        q1         
-------------------
               123
  4567890123456789
               456
  4567890123456789
               123
  4567890123456789
 -4567890123456789
(7 rows)

SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
        q1         
-------------------
 -4567890123456789
               456
(2 rows)

SELECT q1 FROM int8_tbl UNION ALL (((SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1)));
        q1         
-------------------
               123
               123
  4567890123456789
  4567890123456789
  4567890123456789
 -4567890123456789
               456
(7 rows)

(((SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl))) EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
        q1         
-------------------
 -4567890123456789
               456
(2 rows)

--
-- Subqueries with ORDER BY & LIMIT clauses
--
-- In this syntax, ORDER BY/LIMIT apply to the result of the EXCEPT
SELECT q1,q2 FROM int8_tbl EXCEPT SELECT q2,q1 FROM int8_tbl
ORDER BY q2,q1;
        q1        |        q2         
------------------+-------------------
 4567890123456789 | -4567890123456789
              123 |               456
(2 rows)

-- This should fail, because q2 isn't a name of an EXCEPT output column
SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1;
ERROR:  column "q2" does not exist
LINE 1: ... int8_tbl EXCEPT SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1...
                                                             ^
HINT:  There is a column named "q2" in table "*SELECT* 2", but it cannot be referenced from this part of the query.
-- But this should work:
SELECT q1 FROM int8_tbl EXCEPT (((SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1))) ORDER BY 1;
        q1        
------------------
              123
 4567890123456789
(2 rows)

--
-- New syntaxes (7.1) permit new tests
--
(((((select * from int8_tbl)))));
        q1        |        q2         
------------------+-------------------
              123 |               456
              123 |  4567890123456789
 4567890123456789 |               123
 4567890123456789 |  4567890123456789
 4567890123456789 | -4567890123456789
(5 rows)

--
-- Check behavior with empty select list (allowed since 9.4)
--
select union select;
--
(1 row)

select intersect select;
--
(1 row)

select except select;
--
(0 rows)

-- check hashed implementation
set enable_hashagg = true;
set enable_sort = false;
explain (costs off)
select from generate_series(1,5) union select from generate_series(1,3);
                           QUERY PLAN                           
----------------------------------------------------------------
 HashAggregate
   ->  Append
         ->  Function Scan on generate_series
         ->  Function Scan on generate_series generate_series_1
(4 rows)

explain (costs off)
select from generate_series(1,5) intersect select from generate_series(1,3);
                              QUERY PLAN                              
----------------------------------------------------------------------
 HashSetOp Intersect
   ->  Append
         ->  Subquery Scan on "*SELECT* 1"
               ->  Function Scan on generate_series
         ->  Subquery Scan on "*SELECT* 2"
               ->  Function Scan on generate_series generate_series_1
(6 rows)

select from generate_series(1,5) union select from generate_series(1,3);
--
(1 row)

select from generate_series(1,5) union all select from generate_series(1,3);
--
(8 rows)

select from generate_series(1,5) intersect select from generate_series(1,3);
--
(1 row)

select from generate_series(1,5) intersect all select from generate_series(1,3);
--
(3 rows)

select from generate_series(1,5) except select from generate_series(1,3);
--
(0 rows)

select from generate_series(1,5) except all select from generate_series(1,3);
--
(2 rows)

-- check sorted implementation
set enable_hashagg = false;
set enable_sort = true;
explain (costs off)
select from generate_series(1,5) union select from generate_series(1,3);
                           QUERY PLAN                           
----------------------------------------------------------------
 Unique
   ->  Append
         ->  Function Scan on generate_series
         ->  Function Scan on generate_series generate_series_1
(4 rows)

explain (costs off)
select from generate_series(1,5) intersect select from generate_series(1,3);
                              QUERY PLAN                              
----------------------------------------------------------------------
 SetOp Intersect
   ->  Append
         ->  Subquery Scan on "*SELECT* 1"
               ->  Function Scan on generate_series
         ->  Subquery Scan on "*SELECT* 2"
               ->  Function Scan on generate_series generate_series_1
(6 rows)

select from generate_series(1,5) union select from generate_series(1,3);
--
(1 row)

select from generate_series(1,5) union all select from generate_series(1,3);
--
(8 rows)

select from generate_series(1,5) intersect select from generate_series(1,3);
--
(1 row)

select from generate_series(1,5) intersect all select from generate_series(1,3);
--
(3 rows)

select from generate_series(1,5) except select from generate_series(1,3);
--
(0 rows)

select from generate_series(1,5) except all select from generate_series(1,3);
--
(2 rows)

reset enable_hashagg;
reset enable_sort;
--
-- Check handling of a case with unknown constants.  We don't guarantee
-- an undecorated constant will work in all cases, but historically this
-- usage has worked, so test we don't break it.
--
SELECT a.f1 FROM (SELECT 'test' AS f1 FROM varchar_tbl) a
UNION
SELECT b.f1 FROM (SELECT f1 FROM varchar_tbl) b
ORDER BY 1;
  f1  
------
 a
 ab
 abcd
 test
(4 rows)

-- This should fail, but it should produce an error cursor
SELECT '3.4'::numeric UNION SELECT 'foo';
ERROR:  invalid input syntax for type numeric: "foo"
LINE 1: SELECT '3.4'::numeric UNION SELECT 'foo';
                                           ^
--
-- Test that expression-index constraints can be pushed down through
-- UNION or UNION ALL
--
CREATE TEMP TABLE t1 (a text, b text);
CREATE INDEX t1_ab_idx on t1 ((a || b));
CREATE TEMP TABLE t2 (ab text primary key);
INSERT INTO t1 VALUES ('a', 'b'), ('x', 'y');
INSERT INTO t2 VALUES ('ab'), ('xy');
set enable_seqscan = off;
set enable_indexscan = on;
set enable_bitmapscan = off;
explain (costs off)
 SELECT * FROM
 (SELECT a || b AS ab FROM t1
  UNION ALL
  SELECT * FROM t2) t
 WHERE ab = 'ab';
                 QUERY PLAN                  
---------------------------------------------
 Append
   ->  Index Scan using t1_ab_idx on t1
         Index Cond: ((a || b) = 'ab'::text)
   ->  Index Only Scan using t2_pkey on t2
         Index Cond: (ab = 'ab'::text)
(5 rows)

explain (costs off)
 SELECT * FROM
 (SELECT a || b AS ab FROM t1
  UNION
  SELECT * FROM t2) t
 WHERE ab = 'ab';
                    QUERY PLAN                     
---------------------------------------------------
 HashAggregate
   Group Key: ((t1.a || t1.b))
   ->  Append
         ->  Index Scan using t1_ab_idx on t1
               Index Cond: ((a || b) = 'ab'::text)
         ->  Index Only Scan using t2_pkey on t2
               Index Cond: (ab = 'ab'::text)
(7 rows)

--
-- Test that ORDER BY for UNION ALL can be pushed down to inheritance
-- children.
--
CREATE TEMP TABLE t1c (b text, a text);
ALTER TABLE t1c INHERIT t1;
CREATE TEMP TABLE t2c (primary key (ab)) INHERITS (t2);
INSERT INTO t1c VALUES ('v', 'w'), ('c', 'd'), ('m', 'n'), ('e', 'f');
INSERT INTO t2c VALUES ('vw'), ('cd'), ('mn'), ('ef');
CREATE INDEX t1c_ab_idx on t1c ((a || b));
set enable_seqscan = on;
set enable_indexonlyscan = off;
explain (costs off)
  SELECT * FROM
  (SELECT a || b AS ab FROM t1
   UNION ALL
   SELECT ab FROM t2) t
  ORDER BY 1 LIMIT 8;
                     QUERY PLAN                      
-----------------------------------------------------
 Limit
   ->  Merge Append
         Sort Key: ((t1.a || t1.b))
         ->  Index Scan using t1_ab_idx on t1
         ->  Index Scan using t1c_ab_idx on t1c t1_1
         ->  Index Scan using t2_pkey on t2
         ->  Index Scan using t2c_pkey on t2c t2_1
(7 rows)

  SELECT * FROM
  (SELECT a || b AS ab FROM t1
   UNION ALL
   SELECT ab FROM t2) t
  ORDER BY 1 LIMIT 8;
 ab 
----
 ab
 ab
 cd
 dc
 ef
 fe
 mn
 nm
(8 rows)

reset enable_seqscan;
reset enable_indexscan;
reset enable_bitmapscan;
-- This simpler variant of the above test has been observed to fail differently
create table events (event_id int primary key);
create table other_events (event_id int primary key);
create table events_child () inherits (events);
explain (costs off)
select event_id
 from (select event_id from events
       union all
       select event_id from other_events) ss
 order by event_id;
                        QUERY PLAN                        
----------------------------------------------------------
 Merge Append
   Sort Key: events.event_id
   ->  Index Scan using events_pkey on events
   ->  Sort
         Sort Key: events_1.event_id
         ->  Seq Scan on events_child events_1
   ->  Index Scan using other_events_pkey on other_events
(7 rows)

drop table events_child, events, other_events;
reset enable_indexonlyscan;
-- Test constraint exclusion of UNION ALL subqueries
explain (costs off)
 SELECT * FROM
  (SELECT 1 AS t, * FROM tenk1 a
   UNION ALL
   SELECT 2 AS t, * FROM tenk1 b) c
 WHERE t = 2;
     QUERY PLAN      
---------------------
 Seq Scan on tenk1 b
(1 row)

-- Test that we push quals into UNION sub-selects only when it's safe
explain (costs off)
SELECT * FROM
  (SELECT 1 AS t, 2 AS x
   UNION
   SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
                    QUERY PLAN                    
--------------------------------------------------
 Sort
   Sort Key: (2)
   ->  Unique
         ->  Sort
               Sort Key: (1), (2)
               ->  Append
                     ->  Result
                     ->  Result
                           One-Time Filter: false
(9 rows)

SELECT * FROM
  (SELECT 1 AS t, 2 AS x
   UNION
   SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
 t | x 
---+---
 1 | 2
(1 row)

explain (costs off)
SELECT * FROM
  (SELECT 1 AS t, generate_series(1,10) AS x
   UNION
   SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
                       QUERY PLAN                       
--------------------------------------------------------
 Sort
   Sort Key: ss.x
   ->  Subquery Scan on ss
         Filter: (ss.x < 4)
         ->  HashAggregate
               Group Key: (1), (generate_series(1, 10))
               ->  Append
                     ->  ProjectSet
                           ->  Result
                     ->  Result
(10 rows)

SELECT * FROM
  (SELECT 1 AS t, generate_series(1,10) AS x
   UNION
   SELECT 2 AS t, 4 AS x) ss
WHERE x < 4
ORDER BY x;
 t | x 
---+---
 1 | 1
 1 | 2
 1 | 3
(3 rows)

explain (costs off)
SELECT * FROM
  (SELECT 1 AS t, (random()*3)::int AS x
   UNION
   SELECT 2 AS t, 4 AS x) ss
WHERE x > 3
ORDER BY x;
                                     QUERY PLAN                                     
------------------------------------------------------------------------------------
 Sort
   Sort Key: ss.x
   ->  Subquery Scan on ss
         Filter: (ss.x > 3)
         ->  Unique
               ->  Sort
                     Sort Key: (1), (((random() * '3'::double precision))::integer)
                     ->  Append
                           ->  Result
                           ->  Result
(10 rows)

SELECT * FROM
  (SELECT 1 AS t, (random()*3)::int AS x
   UNION
   SELECT 2 AS t, 4 AS x) ss
WHERE x > 3
ORDER BY x;
 t | x 
---+---
 2 | 4
(1 row)

-- Test cases where the native ordering of a sub-select has more pathkeys
-- than the outer query cares about
explain (costs off)
select distinct q1 from
  (select distinct * from int8_tbl i81
   union all
   select distinct * from int8_tbl i82) ss
where q2 = q2;
                        QUERY PLAN                        
----------------------------------------------------------
 Unique
   ->  Merge Append
         Sort Key: "*SELECT* 1".q1
         ->  Subquery Scan on "*SELECT* 1"
               ->  Unique
                     ->  Sort
                           Sort Key: i81.q1, i81.q2
                           ->  Seq Scan on int8_tbl i81
                                 Filter: (q2 IS NOT NULL)
         ->  Subquery Scan on "*SELECT* 2"
               ->  Unique
                     ->  Sort
                           Sort Key: i82.q1, i82.q2
                           ->  Seq Scan on int8_tbl i82
                                 Filter: (q2 IS NOT NULL)
(15 rows)

select distinct q1 from
  (select distinct * from int8_tbl i81
   union all
   select distinct * from int8_tbl i82) ss
where q2 = q2;
        q1        
------------------
              123
 4567890123456789
(2 rows)

explain (costs off)
select distinct q1 from
  (select distinct * from int8_tbl i81
   union all
   select distinct * from int8_tbl i82) ss
where -q1 = q2;
                       QUERY PLAN                       
--------------------------------------------------------
 Unique
   ->  Merge Append
         Sort Key: "*SELECT* 1".q1
         ->  Subquery Scan on "*SELECT* 1"
               ->  Unique
                     ->  Sort
                           Sort Key: i81.q1, i81.q2
                           ->  Seq Scan on int8_tbl i81
                                 Filter: ((- q1) = q2)
         ->  Subquery Scan on "*SELECT* 2"
               ->  Unique
                     ->  Sort
                           Sort Key: i82.q1, i82.q2
                           ->  Seq Scan on int8_tbl i82
                                 Filter: ((- q1) = q2)
(15 rows)

select distinct q1 from
  (select distinct * from int8_tbl i81
   union all
   select distinct * from int8_tbl i82) ss
where -q1 = q2;
        q1        
------------------
 4567890123456789
(1 row)

-- Test proper handling of parameterized appendrel paths when the
-- potential join qual is expensive
create function expensivefunc(int) returns int
language plpgsql immutable strict cost 10000
as $$begin return $1; end$$;
create temp table t3 as select generate_series(-1000,1000) as x;
create index t3i on t3 (expensivefunc(x));
analyze t3;
explain (costs off)
select * from
  (select * from t3 a union all select * from t3 b) ss
  join int4_tbl on f1 = expensivefunc(x);
                         QUERY PLAN                         
------------------------------------------------------------
 Nested Loop
   ->  Seq Scan on int4_tbl
   ->  Append
         ->  Index Scan using t3i on t3 a
               Index Cond: (expensivefunc(x) = int4_tbl.f1)
         ->  Index Scan using t3i on t3 b
               Index Cond: (expensivefunc(x) = int4_tbl.f1)
(7 rows)

select * from
  (select * from t3 a union all select * from t3 b) ss
  join int4_tbl on f1 = expensivefunc(x);
 x | f1 
---+----
 0 |  0
 0 |  0
(2 rows)

drop table t3;
drop function expensivefunc(int);
-- Test handling of appendrel quals that const-simplify into an AND
explain (costs off)
select * from
  (select *, 0 as x from int8_tbl a
   union all
   select *, 1 as x from int8_tbl b) ss
where (x = 0) or (q1 >= q2 and q1 <= q2);
                 QUERY PLAN                  
---------------------------------------------
 Append
   ->  Seq Scan on int8_tbl a
   ->  Seq Scan on int8_tbl b
         Filter: ((q1 >= q2) AND (q1 <= q2))
(4 rows)

select * from
  (select *, 0 as x from int8_tbl a
   union all
   select *, 1 as x from int8_tbl b) ss
where (x = 0) or (q1 >= q2 and q1 <= q2);
        q1        |        q2         | x 
------------------+-------------------+---
              123 |               456 | 0
              123 |  4567890123456789 | 0
 4567890123456789 |               123 | 0
 4567890123456789 |  4567890123456789 | 0
 4567890123456789 | -4567890123456789 | 0
 4567890123456789 |  4567890123456789 | 1
(6 rows)