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--
-- Test returning SETOF
--
CREATE FUNCTION test_setof_error() RETURNS SETOF text AS $$
return 37
$$ LANGUAGE plpython3u;
SELECT test_setof_error();
CREATE FUNCTION test_setof_as_list(count integer, content text) RETURNS SETOF text AS $$
return [ content ]*count
$$ LANGUAGE plpython3u;
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 plpython3u;
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 plpython3u;
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 plpython3u;
-- Test set returning functions
SELECT test_setof_as_list(0, 'list');
SELECT test_setof_as_list(1, 'list');
SELECT test_setof_as_list(2, 'list');
SELECT test_setof_as_list(2, null);
SELECT test_setof_as_tuple(0, 'tuple');
SELECT test_setof_as_tuple(1, 'tuple');
SELECT test_setof_as_tuple(2, 'tuple');
SELECT test_setof_as_tuple(2, null);
SELECT test_setof_as_iterator(0, 'list');
SELECT test_setof_as_iterator(1, 'list');
SELECT test_setof_as_iterator(2, 'list');
SELECT test_setof_as_iterator(2, null);
SELECT test_setof_spi_in_iterator();
-- set-returning function that modifies its parameters
CREATE OR REPLACE FUNCTION ugly(x int, lim int) RETURNS SETOF int AS $$
global x
while x <= lim:
yield x
x = x + 1
$$ LANGUAGE plpython3u;
SELECT ugly(1, 5);
-- interleaved execution of such a function
SELECT ugly(1,3), ugly(7,8);
-- returns set of named-composite-type tuples
CREATE OR REPLACE FUNCTION get_user_records()
RETURNS SETOF users
AS $$
return plpy.execute("SELECT * FROM users ORDER BY username")
$$ LANGUAGE plpython3u;
SELECT get_user_records();
SELECT * FROM get_user_records();
-- same, but returning set of RECORD
CREATE OR REPLACE FUNCTION get_user_records2()
RETURNS TABLE(fname text, lname text, username text, userid int)
AS $$
return plpy.execute("SELECT * FROM users ORDER BY username")
$$ LANGUAGE plpython3u;
SELECT get_user_records2();
SELECT * FROM get_user_records2();
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