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|
--
-- Test returning tuples
--
CREATE TABLE table_record (
first text,
second int4
) ;
CREATE TYPE type_record AS (
first text,
second int4
) ;
CREATE FUNCTION test_table_record_as(typ text, first text, second integer, retnull boolean) RETURNS table_record AS $$
if retnull:
return None
if typ == 'dict':
return { 'first': first, 'second': second, 'additionalfield': 'must not cause trouble' }
elif typ == 'tuple':
return ( first, second )
elif typ == 'list':
return [ first, second ]
elif typ == 'obj':
class type_record: pass
type_record.first = first
type_record.second = second
return type_record
$$ LANGUAGE plpython3u;
CREATE FUNCTION test_type_record_as(typ text, first text, second integer, retnull boolean) RETURNS type_record AS $$
if retnull:
return None
if typ == 'dict':
return { 'first': first, 'second': second, 'additionalfield': 'must not cause trouble' }
elif typ == 'tuple':
return ( first, second )
elif typ == 'list':
return [ first, second ]
elif typ == 'obj':
class type_record: pass
type_record.first = first
type_record.second = second
return type_record
elif typ == 'str':
return "('%s',%r)" % (first, second)
$$ LANGUAGE plpython3u;
CREATE FUNCTION test_in_out_params(first in text, second out text) AS $$
return first + '_in_to_out';
$$ LANGUAGE plpython3u;
CREATE FUNCTION test_in_out_params_multi(first in text,
second out text, third out text) AS $$
return (first + '_record_in_to_out_1', first + '_record_in_to_out_2');
$$ LANGUAGE plpython3u;
CREATE FUNCTION test_inout_params(first inout text) AS $$
return first + '_inout';
$$ LANGUAGE plpython3u;
-- Test tuple returning functions
SELECT * FROM test_table_record_as('dict', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('dict', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_table_record_as('dict', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_table_record_as('dict', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_table_record_as('dict', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('tuple', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('tuple', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_table_record_as('tuple', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_table_record_as('tuple', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_table_record_as('tuple', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('list', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('list', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_table_record_as('list', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_table_record_as('list', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_table_record_as('list', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('obj', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_table_record_as('obj', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_table_record_as('obj', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_table_record_as('obj', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_table_record_as('obj', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('dict', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('dict', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_type_record_as('dict', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_type_record_as('dict', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_type_record_as('dict', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('tuple', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('tuple', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_type_record_as('tuple', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_type_record_as('tuple', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_type_record_as('tuple', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('list', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('list', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_type_record_as('list', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_type_record_as('list', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_type_record_as('list', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('obj', null, null, false);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('obj', 'one', null, false);
first | second
-------+--------
one |
(1 row)
SELECT * FROM test_type_record_as('obj', null, 2, false);
first | second
-------+--------
| 2
(1 row)
SELECT * FROM test_type_record_as('obj', 'three', 3, false);
first | second
-------+--------
three | 3
(1 row)
SELECT * FROM test_type_record_as('obj', null, null, true);
first | second
-------+--------
|
(1 row)
SELECT * FROM test_type_record_as('str', 'one', 1, false);
first | second
-------+--------
'one' | 1
(1 row)
SELECT * FROM test_in_out_params('test_in');
second
-------------------
test_in_in_to_out
(1 row)
SELECT * FROM test_in_out_params_multi('test_in');
second | third
----------------------------+----------------------------
test_in_record_in_to_out_1 | test_in_record_in_to_out_2
(1 row)
SELECT * FROM test_inout_params('test_in');
first
---------------
test_in_inout
(1 row)
-- try changing the return types and call functions again
ALTER TABLE table_record DROP COLUMN first;
ALTER TABLE table_record DROP COLUMN second;
ALTER TABLE table_record ADD COLUMN first text;
ALTER TABLE table_record ADD COLUMN second int4;
SELECT * FROM test_table_record_as('obj', 'one', 1, false);
first | second
-------+--------
one | 1
(1 row)
ALTER TYPE type_record DROP ATTRIBUTE first;
ALTER TYPE type_record DROP ATTRIBUTE second;
ALTER TYPE type_record ADD ATTRIBUTE first text;
ALTER TYPE type_record ADD ATTRIBUTE second int4;
SELECT * FROM test_type_record_as('obj', 'one', 1, false);
first | second
-------+--------
one | 1
(1 row)
-- errors cases
CREATE FUNCTION test_type_record_error1() RETURNS type_record AS $$
return { 'first': 'first' }
$$ LANGUAGE plpython3u;
SELECT * FROM test_type_record_error1();
ERROR: key "second" not found in mapping
HINT: To return null in a column, add the value None to the mapping with the key named after the column.
CONTEXT: while creating return value
PL/Python function "test_type_record_error1"
CREATE FUNCTION test_type_record_error2() RETURNS type_record AS $$
return [ 'first' ]
$$ LANGUAGE plpython3u;
SELECT * FROM test_type_record_error2();
ERROR: length of returned sequence did not match number of columns in row
CONTEXT: while creating return value
PL/Python function "test_type_record_error2"
CREATE FUNCTION test_type_record_error3() RETURNS type_record AS $$
class type_record: pass
type_record.first = 'first'
return type_record
$$ LANGUAGE plpython3u;
SELECT * FROM test_type_record_error3();
ERROR: attribute "second" does not exist in Python object
HINT: To return null in a column, let the returned object have an attribute named after column with value None.
CONTEXT: while creating return value
PL/Python function "test_type_record_error3"
CREATE FUNCTION test_type_record_error4() RETURNS type_record AS $$
return 'foo'
$$ LANGUAGE plpython3u;
SELECT * FROM test_type_record_error4();
ERROR: malformed record literal: "foo"
DETAIL: Missing left parenthesis.
CONTEXT: while creating return value
PL/Python function "test_type_record_error4"
|
