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ef178d38bb493baa49dc0824656e60717e8a8b1d
postgresql/src/test/regress/sql/with.sql
David Rowley ef178d38bb Fix Assert failure in WITH RECURSIVE UNION queries 
If the non-recursive part of a recursive CTE ended up using
TTSOpsBufferHeapTuple as the table slot type, then a duplicate value
could cause an Assert failure in CheckOpSlotCompatibility() when
checking the hash table for the duplicate value.  The expected slot type
for the deform step was TTSOpsMinimalTuple so the Assert failed when the
TTSOpsBufferHeapTuple slot was used.

This is a long-standing bug which we likely didn't notice because it
seems much more likely that the non-recursive term would have required
projection and used a TTSOpsVirtual slot, which CheckOpSlotCompatibility
is ok with.

There doesn't seem to be any harm done here other than the Assert
failure.  Both TTSOpsMinimalTuple and TTSOpsBufferHeapTuple slot types
require tuple deformation, so the EEOP_*_FETCHSOME ExprState step would
have properly existed in the ExprState.

The solution is to pass NULL for the ExecBuildGroupingEqual's 'lops'
parameter.  This means the ExprState's EEOP_*_FETCHSOME step won't
expect a fixed slot type.  This makes CheckOpSlotCompatibility() happy as
no checking is performed when the ExprEvalStep is not expecting a fixed
slot type.

Reported-by: Richard Guo
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAMbWs4-8U9q2LAtf8+ghV11zeUReA3AmrYkxzBEv0vKnDxwkKA@mail.gmail.com
Backpatch-through: 13, all supported versions
2024-12-19 13:13:01 +13:00

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--
-- Tests for common table expressions (WITH query, ... SELECT ...)
--
-- Basic WITH
WITH q1(x,y) AS (SELECT 1,2)
SELECT * FROM q1, q1 AS q2;
-- Multiple uses are evaluated only once
SELECT count(*) FROM (
WITH q1(x) AS (SELECT random() FROM generate_series(1, 5))
SELECT * FROM q1
UNION
SELECT * FROM q1
) ss;
-- WITH RECURSIVE
-- sum of 1..100
WITH RECURSIVE t(n) AS (
VALUES (1)
UNION ALL
SELECT n+1 FROM t WHERE n < 100
)
SELECT sum(n) FROM t;
WITH RECURSIVE t(n) AS (
SELECT (VALUES(1))
UNION ALL
SELECT n+1 FROM t WHERE n < 5
)
SELECT * FROM t;
-- UNION DISTINCT requires hashable type
WITH RECURSIVE t(n) AS (
VALUES (1::money)
UNION
SELECT n+1::money FROM t WHERE n < 100::money
)
SELECT sum(n) FROM t;
-- recursive view
CREATE RECURSIVE VIEW nums (n) AS
VALUES (1)
UNION ALL
SELECT n+1 FROM nums WHERE n < 5;
SELECT * FROM nums;
CREATE OR REPLACE RECURSIVE VIEW nums (n) AS
VALUES (1)
UNION ALL
SELECT n+1 FROM nums WHERE n < 6;
SELECT * FROM nums;
-- This is an infinite loop with UNION ALL, but not with UNION
WITH RECURSIVE t(n) AS (
SELECT 1
UNION
SELECT 10-n FROM t)
SELECT * FROM t;
-- This'd be an infinite loop, but outside query reads only as much as needed
WITH RECURSIVE t(n) AS (
VALUES (1)
UNION ALL
SELECT n+1 FROM t)
SELECT * FROM t LIMIT 10;
-- UNION case should have same property
WITH RECURSIVE t(n) AS (
SELECT 1
UNION
SELECT n+1 FROM t)
SELECT * FROM t LIMIT 10;
-- Test behavior with an unknown-type literal in the WITH
WITH q AS (SELECT 'foo' AS x)
SELECT x, pg_typeof(x) FROM q;
WITH RECURSIVE t(n) AS (
SELECT 'foo'
UNION ALL
SELECT n || ' bar' FROM t WHERE length(n) < 20
)
SELECT n, pg_typeof(n) FROM t;
-- In a perfect world, this would work and resolve the literal as int ...
-- but for now, we have to be content with resolving to text too soon.
WITH RECURSIVE t(n) AS (
SELECT '7'
UNION ALL
SELECT n+1 FROM t WHERE n < 10
)
SELECT n, pg_typeof(n) FROM t;
-- Deeply nested WITH caused a list-munging problem in v13
-- Detection of cross-references and self-references
WITH RECURSIVE w1(c1) AS
(WITH w2(c2) AS
(WITH w3(c3) AS
(WITH w4(c4) AS
(WITH w5(c5) AS
(WITH RECURSIVE w6(c6) AS
(WITH w6(c6) AS
(WITH w8(c8) AS
(SELECT 1)
SELECT * FROM w8)
SELECT * FROM w6)
SELECT * FROM w6)
SELECT * FROM w5)
SELECT * FROM w4)
SELECT * FROM w3)
SELECT * FROM w2)
SELECT * FROM w1;
-- Detection of invalid self-references
WITH RECURSIVE outermost(x) AS (
SELECT 1
UNION (WITH innermost1 AS (
SELECT 2
UNION (WITH innermost2 AS (
SELECT 3
UNION (WITH innermost3 AS (
SELECT 4
UNION (WITH innermost4 AS (
SELECT 5
UNION (WITH innermost5 AS (
SELECT 6
UNION (WITH innermost6 AS
(SELECT 7)
SELECT * FROM innermost6))
SELECT * FROM innermost5))
SELECT * FROM innermost4))
SELECT * FROM innermost3))
SELECT * FROM innermost2))
SELECT * FROM outermost
UNION SELECT * FROM innermost1)
)
SELECT * FROM outermost ORDER BY 1;
--
-- Some examples with a tree
--
-- department structure represented here is as follows:
--
-- ROOT-+->A-+->B-+->C
-- | |
-- | +->D-+->F
-- +->E-+->G
CREATE TEMP TABLE department (
id INTEGER PRIMARY KEY, -- department ID
parent_department INTEGER REFERENCES department, -- upper department ID
name TEXT -- department name
);
INSERT INTO department VALUES (0, NULL, 'ROOT');
INSERT INTO department VALUES (1, 0, 'A');
INSERT INTO department VALUES (2, 1, 'B');
INSERT INTO department VALUES (3, 2, 'C');
INSERT INTO department VALUES (4, 2, 'D');
INSERT INTO department VALUES (5, 0, 'E');
INSERT INTO department VALUES (6, 4, 'F');
INSERT INTO department VALUES (7, 5, 'G');
-- extract all departments under 'A'. Result should be A, B, C, D and F
WITH RECURSIVE subdepartment AS
(
-- non recursive term
SELECT name as root_name, * FROM department WHERE name = 'A'
UNION ALL
-- recursive term
SELECT sd.root_name, d.* FROM department AS d, subdepartment AS sd
WHERE d.parent_department = sd.id
)
SELECT * FROM subdepartment ORDER BY name;
-- extract all departments under 'A' with "level" number
WITH RECURSIVE subdepartment(level, id, parent_department, name) AS
(
-- non recursive term
SELECT 1, * FROM department WHERE name = 'A'
UNION ALL
-- recursive term
SELECT sd.level + 1, d.* FROM department AS d, subdepartment AS sd
WHERE d.parent_department = sd.id
)
SELECT * FROM subdepartment ORDER BY name;
-- extract all departments under 'A' with "level" number.
-- Only shows level 2 or more
WITH RECURSIVE subdepartment(level, id, parent_department, name) AS
(
-- non recursive term
SELECT 1, * FROM department WHERE name = 'A'
UNION ALL
-- recursive term
SELECT sd.level + 1, d.* FROM department AS d, subdepartment AS sd
WHERE d.parent_department = sd.id
)
SELECT * FROM subdepartment WHERE level >= 2 ORDER BY name;
-- "RECURSIVE" is ignored if the query has no self-reference
WITH RECURSIVE subdepartment AS
(
-- note lack of recursive UNION structure
SELECT * FROM department WHERE name = 'A'
)
SELECT * FROM subdepartment ORDER BY name;
-- inside subqueries
SELECT count(*) FROM (
WITH RECURSIVE t(n) AS (
SELECT 1 UNION ALL SELECT n + 1 FROM t WHERE n < 500
)
SELECT * FROM t) AS t WHERE n < (
SELECT count(*) FROM (
WITH RECURSIVE t(n) AS (
SELECT 1 UNION ALL SELECT n + 1 FROM t WHERE n < 100
)
SELECT * FROM t WHERE n < 50000
) AS t WHERE n < 100);
-- use same CTE twice at different subquery levels
WITH q1(x,y) AS (
SELECT hundred, sum(ten) FROM tenk1 GROUP BY hundred
)
SELECT count(*) FROM q1 WHERE y > (SELECT sum(y)/100 FROM q1 qsub);
-- via a VIEW
CREATE TEMPORARY VIEW vsubdepartment AS
WITH RECURSIVE subdepartment AS
(
-- non recursive term
SELECT * FROM department WHERE name = 'A'
UNION ALL
-- recursive term
SELECT d.* FROM department AS d, subdepartment AS sd
WHERE d.parent_department = sd.id
)
SELECT * FROM subdepartment;
SELECT * FROM vsubdepartment ORDER BY name;
-- Check reverse listing
SELECT pg_get_viewdef('vsubdepartment'::regclass);
SELECT pg_get_viewdef('vsubdepartment'::regclass, true);
-- Another reverse-listing example
CREATE VIEW sums_1_100 AS
WITH RECURSIVE t(n) AS (
VALUES (1)
UNION ALL
SELECT n+1 FROM t WHERE n < 100
)
SELECT sum(n) FROM t;
\d+ sums_1_100
-- corner case in which sub-WITH gets initialized first
with recursive q as (
select * from department
union all
(with x as (select * from q)
select * from x)
)
select * from q limit 24;
with recursive q as (
select * from department
union all
(with recursive x as (
select * from department
union all
(select * from q union all select * from x)
)
select * from x)
)
select * from q limit 32;
-- recursive term has sub-UNION
WITH RECURSIVE t(i,j) AS (
VALUES (1,2)
UNION ALL
SELECT t2.i, t.j+1 FROM
(SELECT 2 AS i UNION ALL SELECT 3 AS i) AS t2
JOIN t ON (t2.i = t.i+1))
SELECT * FROM t;
--
-- different tree example
--
CREATE TEMPORARY TABLE tree(
id INTEGER PRIMARY KEY,
parent_id INTEGER REFERENCES tree(id)
);
INSERT INTO tree
VALUES (1, NULL), (2, 1), (3,1), (4,2), (5,2), (6,2), (7,3), (8,3),
(9,4), (10,4), (11,7), (12,7), (13,7), (14, 9), (15,11), (16,11);
--
-- get all paths from "second level" nodes to leaf nodes
--
WITH RECURSIVE t(id, path) AS (
VALUES(1,ARRAY[]::integer[])
UNION ALL
SELECT tree.id, t.path || tree.id
FROM tree JOIN t ON (tree.parent_id = t.id)
)
SELECT t1.*, t2.* FROM t AS t1 JOIN t AS t2 ON
(t1.path[1] = t2.path[1] AND
array_upper(t1.path,1) = 1 AND
array_upper(t2.path,1) > 1)
ORDER BY t1.id, t2.id;
-- just count 'em
WITH RECURSIVE t(id, path) AS (
VALUES(1,ARRAY[]::integer[])
UNION ALL
SELECT tree.id, t.path || tree.id
FROM tree JOIN t ON (tree.parent_id = t.id)
)
SELECT t1.id, count(t2.*) FROM t AS t1 JOIN t AS t2 ON
(t1.path[1] = t2.path[1] AND
array_upper(t1.path,1) = 1 AND
array_upper(t2.path,1) > 1)
GROUP BY t1.id
ORDER BY t1.id;
-- this variant tickled a whole-row-variable bug in 8.4devel
WITH RECURSIVE t(id, path) AS (
VALUES(1,ARRAY[]::integer[])
UNION ALL
SELECT tree.id, t.path || tree.id
FROM tree JOIN t ON (tree.parent_id = t.id)
)
SELECT t1.id, t2.path, t2 FROM t AS t1 JOIN t AS t2 ON
(t1.id=t2.id);
CREATE TEMP TABLE duplicates (a INT NOT NULL);
INSERT INTO duplicates VALUES(1), (1);
-- Try out a recursive UNION case where the non-recursive part's table slot
-- uses TTSOpsBufferHeapTuple and contains duplicate rows.
WITH RECURSIVE cte (a) as (
SELECT a FROM duplicates
UNION
SELECT a FROM cte
)
SELECT a FROM cte;
-- SEARCH clause
create temp table graph0( f int, t int, label text );
insert into graph0 values
(1, 2, 'arc 1 -> 2'),
(1, 3, 'arc 1 -> 3'),
(2, 3, 'arc 2 -> 3'),
(1, 4, 'arc 1 -> 4'),
(4, 5, 'arc 4 -> 5');
explain (verbose, costs off)
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t set seq
select * from search_graph order by seq;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t set seq
select * from search_graph order by seq;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union distinct
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t set seq
select * from search_graph order by seq;
explain (verbose, costs off)
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search breadth first by f, t set seq
select * from search_graph order by seq;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search breadth first by f, t set seq
select * from search_graph order by seq;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union distinct
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search breadth first by f, t set seq
select * from search_graph order by seq;
-- a constant initial value causes issues for EXPLAIN
explain (verbose, costs off)
with recursive test as (
select 1 as x
union all
select x + 1
from test
) search depth first by x set y
select * from test limit 5;
with recursive test as (
select 1 as x
union all
select x + 1
from test
) search depth first by x set y
select * from test limit 5;
explain (verbose, costs off)
with recursive test as (
select 1 as x
union all
select x + 1
from test
) search breadth first by x set y
select * from test limit 5;
with recursive test as (
select 1 as x
union all
select x + 1
from test
) search breadth first by x set y
select * from test limit 5;
-- various syntax errors
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by foo, tar set seq
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t set label
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t, f set seq
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t set seq
select * from search_graph order by seq;
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
(select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t)
) search depth first by f, t set seq
select * from search_graph order by seq;
-- check that we distinguish same CTE name used at different levels
-- (this case could be supported, perhaps, but it isn't today)
with recursive x(col) as (
select 1
union
(with x as (select * from x)
select * from x)
) search depth first by col set seq
select * from x;
-- test ruleutils and view expansion
create temp view v_search as
with recursive search_graph(f, t, label) as (
select * from graph0 g
union all
select g.*
from graph0 g, search_graph sg
where g.f = sg.t
) search depth first by f, t set seq
select f, t, label from search_graph;
select pg_get_viewdef('v_search');
select * from v_search;
--
-- test cycle detection
--
create temp table graph( f int, t int, label text );
insert into graph values
(1, 2, 'arc 1 -> 2'),
(1, 3, 'arc 1 -> 3'),
(2, 3, 'arc 2 -> 3'),
(1, 4, 'arc 1 -> 4'),
(4, 5, 'arc 4 -> 5'),
(5, 1, 'arc 5 -> 1');
with recursive search_graph(f, t, label, is_cycle, path) as (
select *, false, array[row(g.f, g.t)] from graph g
union all
select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
from graph g, search_graph sg
where g.f = sg.t and not is_cycle
)
select * from search_graph;
-- UNION DISTINCT exercises row type hashing support
with recursive search_graph(f, t, label, is_cycle, path) as (
select *, false, array[row(g.f, g.t)] from graph g
union distinct
select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
from graph g, search_graph sg
where g.f = sg.t and not is_cycle
)
select * from search_graph;
-- ordering by the path column has same effect as SEARCH DEPTH FIRST
with recursive search_graph(f, t, label, is_cycle, path) as (
select *, false, array[row(g.f, g.t)] from graph g
union all
select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
from graph g, search_graph sg
where g.f = sg.t and not is_cycle
)
select * from search_graph order by path;
-- CYCLE clause
explain (verbose, costs off)
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union distinct
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle to 'Y' default 'N' using path
select * from search_graph;
explain (verbose, costs off)
with recursive test as (
select 0 as x
union all
select (x + 1) % 10
from test
) cycle x set is_cycle using path
select * from test;
with recursive test as (
select 0 as x
union all
select (x + 1) % 10
from test
) cycle x set is_cycle using path
select * from test;
with recursive test as (
select 0 as x
union all
select (x + 1) % 10
from test
where not is_cycle -- redundant, but legal
) cycle x set is_cycle using path
select * from test;
-- multiple CTEs
with recursive
graph(f, t, label) as (
values (1, 2, 'arc 1 -> 2'),
(1, 3, 'arc 1 -> 3'),
(2, 3, 'arc 2 -> 3'),
(1, 4, 'arc 1 -> 4'),
(4, 5, 'arc 4 -> 5'),
(5, 1, 'arc 5 -> 1')
),
search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle to true default false using path
select f, t, label from search_graph;
-- star expansion
with recursive a as (
select 1 as b
union all
select * from a
) cycle b set c using p
select * from a;
-- search+cycle
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) search depth first by f, t set seq
cycle f, t set is_cycle using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) search breadth first by f, t set seq
cycle f, t set is_cycle using path
select * from search_graph;
-- various syntax errors
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle foo, tar set is_cycle using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle to true default 55 using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle to point '(1,1)' default point '(0,0)' using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set label to true default false using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle to true default false using label
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set foo to true default false using foo
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t, f set is_cycle to true default false using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) search depth first by f, t set foo
cycle f, t set foo to true default false using path
select * from search_graph;
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) search depth first by f, t set foo
cycle f, t set is_cycle to true default false using foo
select * from search_graph;
-- test ruleutils and view expansion
create temp view v_cycle1 as
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle using path
select f, t, label from search_graph;
create temp view v_cycle2 as
with recursive search_graph(f, t, label) as (
select * from graph g
union all
select g.*
from graph g, search_graph sg
where g.f = sg.t
) cycle f, t set is_cycle to 'Y' default 'N' using path
select f, t, label from search_graph;
select pg_get_viewdef('v_cycle1');
select pg_get_viewdef('v_cycle2');
select * from v_cycle1;
select * from v_cycle2;
--
-- test multiple WITH queries
--
WITH RECURSIVE
y (id) AS (VALUES (1)),
x (id) AS (SELECT * FROM y UNION ALL SELECT id+1 FROM x WHERE id < 5)
SELECT * FROM x;
-- forward reference OK
WITH RECURSIVE
x(id) AS (SELECT * FROM y UNION ALL SELECT id+1 FROM x WHERE id < 5),
y(id) AS (values (1))
SELECT * FROM x;
WITH RECURSIVE
x(id) AS
(VALUES (1) UNION ALL SELECT id+1 FROM x WHERE id < 5),
y(id) AS
(VALUES (1) UNION ALL SELECT id+1 FROM y WHERE id < 10)
SELECT y.*, x.* FROM y LEFT JOIN x USING (id);
WITH RECURSIVE
x(id) AS
(VALUES (1) UNION ALL SELECT id+1 FROM x WHERE id < 5),
y(id) AS
(VALUES (1) UNION ALL SELECT id+1 FROM x WHERE id < 10)
SELECT y.*, x.* FROM y LEFT JOIN x USING (id);
WITH RECURSIVE
x(id) AS
(SELECT 1 UNION ALL SELECT id+1 FROM x WHERE id < 3 ),
y(id) AS
(SELECT * FROM x UNION ALL SELECT * FROM x),
z(id) AS
(SELECT * FROM x UNION ALL SELECT id+1 FROM z WHERE id < 10)
SELECT * FROM z;
WITH RECURSIVE
x(id) AS
(SELECT 1 UNION ALL SELECT id+1 FROM x WHERE id < 3 ),
y(id) AS
(SELECT * FROM x UNION ALL SELECT * FROM x),
z(id) AS
(SELECT * FROM y UNION ALL SELECT id+1 FROM z WHERE id < 10)
SELECT * FROM z;
--
-- Test WITH attached to a data-modifying statement
--
CREATE TEMPORARY TABLE y (a INTEGER);
INSERT INTO y SELECT generate_series(1, 10);
WITH t AS (
SELECT a FROM y
)
INSERT INTO y
SELECT a+20 FROM t RETURNING *;
SELECT * FROM y;
WITH t AS (
SELECT a FROM y
)
UPDATE y SET a = y.a-10 FROM t WHERE y.a > 20 AND t.a = y.a RETURNING y.a;
SELECT * FROM y;
WITH RECURSIVE t(a) AS (
SELECT 11
UNION ALL
SELECT a+1 FROM t WHERE a < 50
)
DELETE FROM y USING t WHERE t.a = y.a RETURNING y.a;
SELECT * FROM y;
DROP TABLE y;
--
-- error cases
--
WITH x(n, b) AS (SELECT 1)
SELECT * FROM x;
-- INTERSECT
WITH RECURSIVE x(n) AS (SELECT 1 INTERSECT SELECT n+1 FROM x)
SELECT * FROM x;
WITH RECURSIVE x(n) AS (SELECT 1 INTERSECT ALL SELECT n+1 FROM x)
SELECT * FROM x;
-- EXCEPT
WITH RECURSIVE x(n) AS (SELECT 1 EXCEPT SELECT n+1 FROM x)
SELECT * FROM x;
WITH RECURSIVE x(n) AS (SELECT 1 EXCEPT ALL SELECT n+1 FROM x)
SELECT * FROM x;
-- no non-recursive term
WITH RECURSIVE x(n) AS (SELECT n FROM x)
SELECT * FROM x;
-- recursive term in the left hand side (strictly speaking, should allow this)
WITH RECURSIVE x(n) AS (SELECT n FROM x UNION ALL SELECT 1)
SELECT * FROM x;
-- allow this, because we historically have
WITH RECURSIVE x(n) AS (
WITH x1 AS (SELECT 1 AS n)
SELECT 0
UNION
SELECT * FROM x1)
SELECT * FROM x;
-- but this should be rejected
WITH RECURSIVE x(n) AS (
WITH x1 AS (SELECT 1 FROM x)
SELECT 0
UNION
SELECT * FROM x1)
SELECT * FROM x;
-- and this too
WITH RECURSIVE x(n) AS (
(WITH x1 AS (SELECT 1 FROM x) SELECT * FROM x1)
UNION
SELECT 0)
SELECT * FROM x;
-- and this
WITH RECURSIVE x(n) AS (
SELECT 0 UNION SELECT 1
ORDER BY (SELECT n FROM x))
SELECT * FROM x;
CREATE TEMPORARY TABLE y (a INTEGER);
INSERT INTO y SELECT generate_series(1, 10);
-- LEFT JOIN
WITH RECURSIVE x(n) AS (SELECT a FROM y WHERE a = 1
UNION ALL
SELECT x.n+1 FROM y LEFT JOIN x ON x.n = y.a WHERE n < 10)
SELECT * FROM x;
-- RIGHT JOIN
WITH RECURSIVE x(n) AS (SELECT a FROM y WHERE a = 1
UNION ALL
SELECT x.n+1 FROM x RIGHT JOIN y ON x.n = y.a WHERE n < 10)
SELECT * FROM x;
-- FULL JOIN
WITH RECURSIVE x(n) AS (SELECT a FROM y WHERE a = 1
UNION ALL
SELECT x.n+1 FROM x FULL JOIN y ON x.n = y.a WHERE n < 10)
SELECT * FROM x;
-- subquery
WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT n+1 FROM x
WHERE n IN (SELECT * FROM x))
SELECT * FROM x;
-- aggregate functions
WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT count(*) FROM x)
SELECT * FROM x;
WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT sum(n) FROM x)
SELECT * FROM x;
-- ORDER BY
WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT n+1 FROM x ORDER BY 1)
SELECT * FROM x;
-- LIMIT/OFFSET
WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT n+1 FROM x LIMIT 10 OFFSET 1)
SELECT * FROM x;
-- FOR UPDATE
WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT n+1 FROM x FOR UPDATE)
SELECT * FROM x;
-- target list has a recursive query name
WITH RECURSIVE x(id) AS (values (1)
UNION ALL
SELECT (SELECT * FROM x) FROM x WHERE id < 5
) SELECT * FROM x;
-- mutual recursive query (not implemented)
WITH RECURSIVE
x (id) AS (SELECT 1 UNION ALL SELECT id+1 FROM y WHERE id < 5),
y (id) AS (SELECT 1 UNION ALL SELECT id+1 FROM x WHERE id < 5)
SELECT * FROM x;
-- non-linear recursion is not allowed
WITH RECURSIVE foo(i) AS
(values (1)
UNION ALL
(SELECT i+1 FROM foo WHERE i < 10
UNION ALL
SELECT i+1 FROM foo WHERE i < 5)
) SELECT * FROM foo;
WITH RECURSIVE foo(i) AS
(values (1)
UNION ALL
SELECT * FROM
(SELECT i+1 FROM foo WHERE i < 10
UNION ALL
SELECT i+1 FROM foo WHERE i < 5) AS t
) SELECT * FROM foo;
WITH RECURSIVE foo(i) AS
(values (1)
UNION ALL
(SELECT i+1 FROM foo WHERE i < 10
EXCEPT
SELECT i+1 FROM foo WHERE i < 5)
) SELECT * FROM foo;
WITH RECURSIVE foo(i) AS
(values (1)
UNION ALL
(SELECT i+1 FROM foo WHERE i < 10
INTERSECT
SELECT i+1 FROM foo WHERE i < 5)
) SELECT * FROM foo;
-- Wrong type induced from non-recursive term
WITH RECURSIVE foo(i) AS
(SELECT i FROM (VALUES(1),(2)) t(i)
UNION ALL
SELECT (i+1)::numeric(10,0) FROM foo WHERE i < 10)
SELECT * FROM foo;
-- rejects different typmod, too (should we allow this?)
WITH RECURSIVE foo(i) AS
(SELECT i::numeric(3,0) FROM (VALUES(1),(2)) t(i)
UNION ALL
SELECT (i+1)::numeric(10,0) FROM foo WHERE i < 10)
SELECT * FROM foo;
-- disallow OLD/NEW reference in CTE
CREATE TEMPORARY TABLE x (n integer);
CREATE RULE r2 AS ON UPDATE TO x DO INSTEAD
WITH t AS (SELECT OLD.*) UPDATE y SET a = t.n FROM t;
--
-- test for bug #4902
--
with cte(foo) as ( values(42) ) values((select foo from cte));
with cte(foo) as ( select 42 ) select * from ((select foo from cte)) q;
-- test CTE referencing an outer-level variable (to see that changed-parameter
-- signaling still works properly after fixing this bug)
select ( with cte(foo) as ( values(f1) )
select (select foo from cte) )
from int4_tbl;
select ( with cte(foo) as ( values(f1) )
values((select foo from cte)) )
from int4_tbl;
--
-- test for nested-recursive-WITH bug
--
WITH RECURSIVE t(j) AS (
WITH RECURSIVE s(i) AS (
VALUES (1)
UNION ALL
SELECT i+1 FROM s WHERE i < 10
)
SELECT i FROM s
UNION ALL
SELECT j+1 FROM t WHERE j < 10
)
SELECT * FROM t;
--
-- test WITH attached to intermediate-level set operation
--
WITH outermost(x) AS (
SELECT 1
UNION (WITH innermost as (SELECT 2)
SELECT * FROM innermost
UNION SELECT 3)
)
SELECT * FROM outermost ORDER BY 1;
WITH outermost(x) AS (
SELECT 1
UNION (WITH innermost as (SELECT 2)
SELECT * FROM outermost -- fail
UNION SELECT * FROM innermost)
)
SELECT * FROM outermost ORDER BY 1;
WITH RECURSIVE outermost(x) AS (
SELECT 1
UNION (WITH innermost as (SELECT 2)
SELECT * FROM outermost
UNION SELECT * FROM innermost)
)
SELECT * FROM outermost ORDER BY 1;
WITH RECURSIVE outermost(x) AS (
WITH innermost as (SELECT 2 FROM outermost) -- fail
SELECT * FROM innermost
UNION SELECT * from outermost
)
SELECT * FROM outermost ORDER BY 1;
--
-- This test will fail with the old implementation of PARAM_EXEC parameter
-- assignment, because the "q1" Var passed down to A's targetlist subselect
-- looks exactly like the "A.id" Var passed down to C's subselect, causing
-- the old code to give them the same runtime PARAM_EXEC slot. But the
-- lifespans of the two parameters overlap, thanks to B also reading A.
--
with
A as ( select q2 as id, (select q1) as x from int8_tbl ),
B as ( select id, row_number() over (partition by id) as r from A ),
C as ( select A.id, array(select B.id from B where B.id = A.id) from A )
select * from C;
--
-- Test CTEs read in non-initialization orders
--
WITH RECURSIVE
tab(id_key,link) AS (VALUES (1,17), (2,17), (3,17), (4,17), (6,17), (5,17)),
iter (id_key, row_type, link) AS (
SELECT 0, 'base', 17
UNION ALL (
WITH remaining(id_key, row_type, link, min) AS (
SELECT tab.id_key, 'true'::text, iter.link, MIN(tab.id_key) OVER ()
FROM tab INNER JOIN iter USING (link)
WHERE tab.id_key > iter.id_key
),
first_remaining AS (
SELECT id_key, row_type, link
FROM remaining
WHERE id_key=min
),
effect AS (
SELECT tab.id_key, 'new'::text, tab.link
FROM first_remaining e INNER JOIN tab ON e.id_key=tab.id_key
WHERE e.row_type = 'false'
)
SELECT * FROM first_remaining
UNION ALL SELECT * FROM effect
)
)
SELECT * FROM iter;
WITH RECURSIVE
tab(id_key,link) AS (VALUES (1,17), (2,17), (3,17), (4,17), (6,17), (5,17)),
iter (id_key, row_type, link) AS (
SELECT 0, 'base', 17
UNION (
WITH remaining(id_key, row_type, link, min) AS (
SELECT tab.id_key, 'true'::text, iter.link, MIN(tab.id_key) OVER ()
FROM tab INNER JOIN iter USING (link)
WHERE tab.id_key > iter.id_key
),
first_remaining AS (
SELECT id_key, row_type, link
FROM remaining
WHERE id_key=min
),
effect AS (
SELECT tab.id_key, 'new'::text, tab.link
FROM first_remaining e INNER JOIN tab ON e.id_key=tab.id_key
WHERE e.row_type = 'false'
)
SELECT * FROM first_remaining
UNION ALL SELECT * FROM effect
)
)
SELECT * FROM iter;
--
-- Data-modifying statements in WITH
--
-- INSERT ... RETURNING
WITH t AS (
INSERT INTO y
VALUES
(11),
(12),
(13),
(14),
(15),
(16),
(17),
(18),
(19),
(20)
RETURNING *
)
SELECT * FROM t;
SELECT * FROM y;
-- UPDATE ... RETURNING
WITH t AS (
UPDATE y
SET a=a+1
RETURNING *
)
SELECT * FROM t;
SELECT * FROM y;
-- DELETE ... RETURNING
WITH t AS (
DELETE FROM y
WHERE a <= 10
RETURNING *
)
SELECT * FROM t;
SELECT * FROM y;
-- forward reference
WITH RECURSIVE t AS (
INSERT INTO y
SELECT a+5 FROM t2 WHERE a > 5
RETURNING *
), t2 AS (
UPDATE y SET a=a-11 RETURNING *
)
SELECT * FROM t
UNION ALL
SELECT * FROM t2;
SELECT * FROM y;
-- unconditional DO INSTEAD rule
CREATE RULE y_rule AS ON DELETE TO y DO INSTEAD
INSERT INTO y VALUES(42) RETURNING *;
WITH t AS (
DELETE FROM y RETURNING *
)
SELECT * FROM t;
SELECT * FROM y;
DROP RULE y_rule ON y;
-- check merging of outer CTE with CTE in a rule action
CREATE TEMP TABLE bug6051 AS
select i from generate_series(1,3) as t(i);
SELECT * FROM bug6051;
WITH t1 AS ( DELETE FROM bug6051 RETURNING * )
INSERT INTO bug6051 SELECT * FROM t1;
SELECT * FROM bug6051;
CREATE TEMP TABLE bug6051_2 (i int);
CREATE RULE bug6051_ins AS ON INSERT TO bug6051 DO INSTEAD
INSERT INTO bug6051_2
VALUES(NEW.i);
WITH t1 AS ( DELETE FROM bug6051 RETURNING * )
INSERT INTO bug6051 SELECT * FROM t1;
SELECT * FROM bug6051;
SELECT * FROM bug6051_2;
-- check INSERT...SELECT rule actions are disallowed on commands
-- that have modifyingCTEs
CREATE OR REPLACE RULE bug6051_ins AS ON INSERT TO bug6051 DO INSTEAD
INSERT INTO bug6051_2
SELECT NEW.i;
WITH t1 AS ( DELETE FROM bug6051 RETURNING * )
INSERT INTO bug6051 SELECT * FROM t1;
-- silly example to verify that hasModifyingCTE flag is propagated
CREATE TEMP TABLE bug6051_3 AS
SELECT a FROM generate_series(11,13) AS a;
CREATE RULE bug6051_3_ins AS ON INSERT TO bug6051_3 DO INSTEAD
SELECT i FROM bug6051_2;
BEGIN; SET LOCAL force_parallel_mode = on;
WITH t1 AS ( DELETE FROM bug6051_3 RETURNING * )
INSERT INTO bug6051_3 SELECT * FROM t1;
COMMIT;
SELECT * FROM bug6051_3;
-- check case where CTE reference is removed due to optimization
EXPLAIN (VERBOSE, COSTS OFF)
SELECT q1 FROM
(
WITH t_cte AS (SELECT * FROM int8_tbl t)
SELECT q1, (SELECT q2 FROM t_cte WHERE t_cte.q1 = i8.q1) AS t_sub
FROM int8_tbl i8
) ss;
SELECT q1 FROM
(
WITH t_cte AS (SELECT * FROM int8_tbl t)
SELECT q1, (SELECT q2 FROM t_cte WHERE t_cte.q1 = i8.q1) AS t_sub
FROM int8_tbl i8
) ss;
EXPLAIN (VERBOSE, COSTS OFF)
SELECT q1 FROM
(
WITH t_cte AS MATERIALIZED (SELECT * FROM int8_tbl t)
SELECT q1, (SELECT q2 FROM t_cte WHERE t_cte.q1 = i8.q1) AS t_sub
FROM int8_tbl i8
) ss;
SELECT q1 FROM
(
WITH t_cte AS MATERIALIZED (SELECT * FROM int8_tbl t)
SELECT q1, (SELECT q2 FROM t_cte WHERE t_cte.q1 = i8.q1) AS t_sub
FROM int8_tbl i8
) ss;
-- a truly recursive CTE in the same list
WITH RECURSIVE t(a) AS (
SELECT 0
UNION ALL
SELECT a+1 FROM t WHERE a+1 < 5
), t2 as (
INSERT INTO y
SELECT * FROM t RETURNING *
)
SELECT * FROM t2 JOIN y USING (a) ORDER BY a;
SELECT * FROM y;
-- data-modifying WITH in a modifying statement
WITH t AS (
DELETE FROM y
WHERE a <= 10
RETURNING *
)
INSERT INTO y SELECT -a FROM t RETURNING *;
SELECT * FROM y;
-- check that WITH query is run to completion even if outer query isn't
WITH t AS (
UPDATE y SET a = a * 100 RETURNING *
)
SELECT * FROM t LIMIT 10;
SELECT * FROM y;
-- data-modifying WITH containing INSERT...ON CONFLICT DO UPDATE
CREATE TABLE withz AS SELECT i AS k, (i || ' v')::text v FROM generate_series(1, 16, 3) i;
ALTER TABLE withz ADD UNIQUE (k);
WITH t AS (
INSERT INTO withz SELECT i, 'insert'
FROM generate_series(0, 16) i
ON CONFLICT (k) DO UPDATE SET v = withz.v || ', now update'
RETURNING *
)
SELECT * FROM t JOIN y ON t.k = y.a ORDER BY a, k;
-- Test EXCLUDED.* reference within CTE
WITH aa AS (
INSERT INTO withz VALUES(1, 5) ON CONFLICT (k) DO UPDATE SET v = EXCLUDED.v
WHERE withz.k != EXCLUDED.k
RETURNING *
)
SELECT * FROM aa;
-- New query/snapshot demonstrates side-effects of previous query.
SELECT * FROM withz ORDER BY k;
--
-- Ensure subqueries within the update clause work, even if they
-- reference outside values
--
WITH aa AS (SELECT 1 a, 2 b)
INSERT INTO withz VALUES(1, 'insert')
ON CONFLICT (k) DO UPDATE SET v = (SELECT b || ' update' FROM aa WHERE a = 1 LIMIT 1);
WITH aa AS (SELECT 1 a, 2 b)
INSERT INTO withz VALUES(1, 'insert')
ON CONFLICT (k) DO UPDATE SET v = ' update' WHERE withz.k = (SELECT a FROM aa);
WITH aa AS (SELECT 1 a, 2 b)
INSERT INTO withz VALUES(1, 'insert')
ON CONFLICT (k) DO UPDATE SET v = (SELECT b || ' update' FROM aa WHERE a = 1 LIMIT 1);
WITH aa AS (SELECT 'a' a, 'b' b UNION ALL SELECT 'a' a, 'b' b)
INSERT INTO withz VALUES(1, 'insert')
ON CONFLICT (k) DO UPDATE SET v = (SELECT b || ' update' FROM aa WHERE a = 'a' LIMIT 1);
WITH aa AS (SELECT 1 a, 2 b)
INSERT INTO withz VALUES(1, (SELECT b || ' insert' FROM aa WHERE a = 1 ))
ON CONFLICT (k) DO UPDATE SET v = (SELECT b || ' update' FROM aa WHERE a = 1 LIMIT 1);
-- Update a row more than once, in different parts of a wCTE. That is
-- an allowed, presumably very rare, edge case, but since it was
-- broken in the past, having a test seems worthwhile.
WITH simpletup AS (
SELECT 2 k, 'Green' v),
upsert_cte AS (
INSERT INTO withz VALUES(2, 'Blue') ON CONFLICT (k) DO
UPDATE SET (k, v) = (SELECT k, v FROM simpletup WHERE simpletup.k = withz.k)
RETURNING k, v)
INSERT INTO withz VALUES(2, 'Red') ON CONFLICT (k) DO
UPDATE SET (k, v) = (SELECT k, v FROM upsert_cte WHERE upsert_cte.k = withz.k)
RETURNING k, v;
DROP TABLE withz;
-- WITH referenced by MERGE statement
CREATE TABLE m AS SELECT i AS k, (i || ' v')::text v FROM generate_series(1, 16, 3) i;
ALTER TABLE m ADD UNIQUE (k);
WITH RECURSIVE cte_basic AS (SELECT 1 a, 'cte_basic val' b)
MERGE INTO m USING (select 0 k, 'merge source SubPlan' v) o ON m.k=o.k
WHEN MATCHED THEN UPDATE SET v = (SELECT b || ' merge update' FROM cte_basic WHERE cte_basic.a = m.k LIMIT 1)
WHEN NOT MATCHED THEN INSERT VALUES(o.k, o.v);
-- Basic:
WITH cte_basic AS MATERIALIZED (SELECT 1 a, 'cte_basic val' b)
MERGE INTO m USING (select 0 k, 'merge source SubPlan' v offset 0) o ON m.k=o.k
WHEN MATCHED THEN UPDATE SET v = (SELECT b || ' merge update' FROM cte_basic WHERE cte_basic.a = m.k LIMIT 1)
WHEN NOT MATCHED THEN INSERT VALUES(o.k, o.v);
-- Examine
SELECT * FROM m where k = 0;
-- See EXPLAIN output for same query:
EXPLAIN (VERBOSE, COSTS OFF)
WITH cte_basic AS MATERIALIZED (SELECT 1 a, 'cte_basic val' b)
MERGE INTO m USING (select 0 k, 'merge source SubPlan' v offset 0) o ON m.k=o.k
WHEN MATCHED THEN UPDATE SET v = (SELECT b || ' merge update' FROM cte_basic WHERE cte_basic.a = m.k LIMIT 1)
WHEN NOT MATCHED THEN INSERT VALUES(o.k, o.v);
-- InitPlan
WITH cte_init AS MATERIALIZED (SELECT 1 a, 'cte_init val' b)
MERGE INTO m USING (select 1 k, 'merge source InitPlan' v offset 0) o ON m.k=o.k
WHEN MATCHED THEN UPDATE SET v = (SELECT b || ' merge update' FROM cte_init WHERE a = 1 LIMIT 1)
WHEN NOT MATCHED THEN INSERT VALUES(o.k, o.v);
-- Examine
SELECT * FROM m where k = 1;
-- See EXPLAIN output for same query:
EXPLAIN (VERBOSE, COSTS OFF)
WITH cte_init AS MATERIALIZED (SELECT 1 a, 'cte_init val' b)
MERGE INTO m USING (select 1 k, 'merge source InitPlan' v offset 0) o ON m.k=o.k
WHEN MATCHED THEN UPDATE SET v = (SELECT b || ' merge update' FROM cte_init WHERE a = 1 LIMIT 1)
WHEN NOT MATCHED THEN INSERT VALUES(o.k, o.v);
-- MERGE source comes from CTE:
WITH merge_source_cte AS MATERIALIZED (SELECT 15 a, 'merge_source_cte val' b)
MERGE INTO m USING (select * from merge_source_cte) o ON m.k=o.a
WHEN MATCHED THEN UPDATE SET v = (SELECT b || merge_source_cte.*::text || ' merge update' FROM merge_source_cte WHERE a = 15)
WHEN NOT MATCHED THEN INSERT VALUES(o.a, o.b || (SELECT merge_source_cte.*::text || ' merge insert' FROM merge_source_cte));
-- Examine
SELECT * FROM m where k = 15;
-- See EXPLAIN output for same query:
EXPLAIN (VERBOSE, COSTS OFF)
WITH merge_source_cte AS MATERIALIZED (SELECT 15 a, 'merge_source_cte val' b)
MERGE INTO m USING (select * from merge_source_cte) o ON m.k=o.a
WHEN MATCHED THEN UPDATE SET v = (SELECT b || merge_source_cte.*::text || ' merge update' FROM merge_source_cte WHERE a = 15)
WHEN NOT MATCHED THEN INSERT VALUES(o.a, o.b || (SELECT merge_source_cte.*::text || ' merge insert' FROM merge_source_cte));
DROP TABLE m;
-- check that run to completion happens in proper ordering
TRUNCATE TABLE y;
INSERT INTO y SELECT generate_series(1, 3);
CREATE TEMPORARY TABLE yy (a INTEGER);
WITH RECURSIVE t1 AS (
INSERT INTO y SELECT * FROM y RETURNING *
), t2 AS (
INSERT INTO yy SELECT * FROM t1 RETURNING *
)
SELECT 1;
SELECT * FROM y;
SELECT * FROM yy;
WITH RECURSIVE t1 AS (
INSERT INTO yy SELECT * FROM t2 RETURNING *
), t2 AS (
INSERT INTO y SELECT * FROM y RETURNING *
)
SELECT 1;
SELECT * FROM y;
SELECT * FROM yy;
-- triggers
TRUNCATE TABLE y;
INSERT INTO y SELECT generate_series(1, 10);
CREATE FUNCTION y_trigger() RETURNS trigger AS $$
begin
raise notice 'y_trigger: a = %', new.a;
return new;
end;
$$ LANGUAGE plpgsql;
CREATE TRIGGER y_trig BEFORE INSERT ON y FOR EACH ROW
EXECUTE PROCEDURE y_trigger();
WITH t AS (
INSERT INTO y
VALUES
(21),
(22),
(23)
RETURNING *
)
SELECT * FROM t;
SELECT * FROM y;
DROP TRIGGER y_trig ON y;
CREATE TRIGGER y_trig AFTER INSERT ON y FOR EACH ROW
EXECUTE PROCEDURE y_trigger();
WITH t AS (
INSERT INTO y
VALUES
(31),
(32),
(33)
RETURNING *
)
SELECT * FROM t LIMIT 1;
SELECT * FROM y;
DROP TRIGGER y_trig ON y;
CREATE OR REPLACE FUNCTION y_trigger() RETURNS trigger AS $$
begin
raise notice 'y_trigger';
return null;
end;
$$ LANGUAGE plpgsql;
CREATE TRIGGER y_trig AFTER INSERT ON y FOR EACH STATEMENT
EXECUTE PROCEDURE y_trigger();
WITH t AS (
INSERT INTO y
VALUES
(41),
(42),
(43)
RETURNING *
)
SELECT * FROM t;
SELECT * FROM y;
DROP TRIGGER y_trig ON y;
DROP FUNCTION y_trigger();
-- WITH attached to inherited UPDATE or DELETE
CREATE TEMP TABLE parent ( id int, val text );
CREATE TEMP TABLE child1 ( ) INHERITS ( parent );
CREATE TEMP TABLE child2 ( ) INHERITS ( parent );
INSERT INTO parent VALUES ( 1, 'p1' );
INSERT INTO child1 VALUES ( 11, 'c11' ),( 12, 'c12' );
INSERT INTO child2 VALUES ( 23, 'c21' ),( 24, 'c22' );
WITH rcte AS ( SELECT sum(id) AS totalid FROM parent )
UPDATE parent SET id = id + totalid FROM rcte;
SELECT * FROM parent;
WITH wcte AS ( INSERT INTO child1 VALUES ( 42, 'new' ) RETURNING id AS newid )
UPDATE parent SET id = id + newid FROM wcte;
SELECT * FROM parent;
WITH rcte AS ( SELECT max(id) AS maxid FROM parent )
DELETE FROM parent USING rcte WHERE id = maxid;
SELECT * FROM parent;
WITH wcte AS ( INSERT INTO child2 VALUES ( 42, 'new2' ) RETURNING id AS newid )
DELETE FROM parent USING wcte WHERE id = newid;
SELECT * FROM parent;
-- check EXPLAIN VERBOSE for a wCTE with RETURNING
EXPLAIN (VERBOSE, COSTS OFF)
WITH wcte AS ( INSERT INTO int8_tbl VALUES ( 42, 47 ) RETURNING q2 )
DELETE FROM a_star USING wcte WHERE aa = q2;
-- error cases
-- data-modifying WITH tries to use its own output
WITH RECURSIVE t AS (
INSERT INTO y
SELECT * FROM t
)
VALUES(FALSE);
-- no RETURNING in a referenced data-modifying WITH
WITH t AS (
INSERT INTO y VALUES(0)
)
SELECT * FROM t;
-- data-modifying WITH allowed only at the top level
SELECT * FROM (
WITH t AS (UPDATE y SET a=a+1 RETURNING *)
SELECT * FROM t
) ss;
-- most variants of rules aren't allowed
CREATE RULE y_rule AS ON INSERT TO y WHERE a=0 DO INSTEAD DELETE FROM y;
WITH t AS (
INSERT INTO y VALUES(0)
)
VALUES(FALSE);
CREATE OR REPLACE RULE y_rule AS ON INSERT TO y DO INSTEAD NOTHING;
WITH t AS (
INSERT INTO y VALUES(0)
)
VALUES(FALSE);
CREATE OR REPLACE RULE y_rule AS ON INSERT TO y DO INSTEAD NOTIFY foo;
WITH t AS (
INSERT INTO y VALUES(0)
)
VALUES(FALSE);
CREATE OR REPLACE RULE y_rule AS ON INSERT TO y DO ALSO NOTIFY foo;
WITH t AS (
INSERT INTO y VALUES(0)
)
VALUES(FALSE);
CREATE OR REPLACE RULE y_rule AS ON INSERT TO y
DO INSTEAD (NOTIFY foo; NOTIFY bar);
WITH t AS (
INSERT INTO y VALUES(0)
)
VALUES(FALSE);
DROP RULE y_rule ON y;
-- check that parser lookahead for WITH doesn't cause any odd behavior
create table foo (with baz); -- fail, WITH is a reserved word
create table foo (with ordinality); -- fail, WITH is a reserved word
with ordinality as (select 1 as x) select * from ordinality;
-- check sane response to attempt to modify CTE relation
WITH with_test AS (SELECT 42) INSERT INTO with_test VALUES (1);
-- check response to attempt to modify table with same name as a CTE (perhaps
-- surprisingly it works, because CTEs don't hide tables from data-modifying
-- statements)
create temp table with_test (i int);
with with_test as (select 42) insert into with_test select * from with_test;
select * from with_test;
drop table with_test;
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