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--
-- Test returning SETOF
--
CREATE FUNCTION test_setof_error() RETURNS SETOF text AS $$
return 37
$$ LANGUAGE plpythonu;
SELECT test_setof_error();
ERROR: returned object cannot be iterated
DETAIL: PL/Python set-returning functions must return an iterable object.
CONTEXT: PL/Python function "test_setof_error"
CREATE FUNCTION test_setof_as_list(count integer, content text) RETURNS SETOF text AS $$
return [ content ]*count
$$ LANGUAGE plpythonu;
CREATE FUNCTION test_setof_as_tuple(count integer, content text) RETURNS SETOF text AS $$
t = ()
for i in range(count):
t += ( content, )
return t
$$ LANGUAGE plpythonu;
CREATE FUNCTION test_setof_as_iterator(count integer, content text) RETURNS SETOF text AS $$
class producer:
def __init__ (self, icount, icontent):
self.icontent = icontent
self.icount = icount
def __iter__ (self):
return self
def next (self):
if self.icount == 0:
raise StopIteration
self.icount -= 1
return self.icontent
return producer(count, content)
$$ LANGUAGE plpythonu;
CREATE FUNCTION test_setof_spi_in_iterator() RETURNS SETOF text AS
$$
for s in ('Hello', 'Brave', 'New', 'World'):
plpy.execute('select 1')
yield s
plpy.execute('select 2')
$$
LANGUAGE plpythonu;
-- Test set returning functions
SELECT test_setof_as_list(0, 'list');
test_setof_as_list
--------------------
(0 rows)
SELECT test_setof_as_list(1, 'list');
test_setof_as_list
--------------------
list
(1 row)
SELECT test_setof_as_list(2, 'list');
test_setof_as_list
--------------------
list
list
(2 rows)
SELECT test_setof_as_list(2, null);
test_setof_as_list
--------------------
(2 rows)
SELECT test_setof_as_tuple(0, 'tuple');
test_setof_as_tuple
---------------------
(0 rows)
SELECT test_setof_as_tuple(1, 'tuple');
test_setof_as_tuple
---------------------
tuple
(1 row)
SELECT test_setof_as_tuple(2, 'tuple');
test_setof_as_tuple
---------------------
tuple
tuple
(2 rows)
SELECT test_setof_as_tuple(2, null);
test_setof_as_tuple
---------------------
(2 rows)
SELECT test_setof_as_iterator(0, 'list');
test_setof_as_iterator
------------------------
(0 rows)
SELECT test_setof_as_iterator(1, 'list');
test_setof_as_iterator
------------------------
list
(1 row)
SELECT test_setof_as_iterator(2, 'list');
test_setof_as_iterator
------------------------
list
list
(2 rows)
SELECT test_setof_as_iterator(2, null);
test_setof_as_iterator
------------------------
(2 rows)
SELECT test_setof_spi_in_iterator();
test_setof_spi_in_iterator
----------------------------
Hello
Brave
New
World
(4 rows)
-- setof function with an SPI result set (used to crash because of
-- memory management issues across multiple calls)
CREATE OR REPLACE FUNCTION get_user_records()
RETURNS SETOF users
AS $$
return plpy.execute("SELECT * FROM users ORDER BY username")
$$ LANGUAGE plpythonu;
SELECT get_user_records();
get_user_records
----------------------
(jane,doe,j_doe,1)
(john,doe,johnd,2)
(rick,smith,slash,4)
(willem,doe,w_doe,3)
(4 rows)
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