Обсуждение: BUG #5128: Returning nested composite types in plpython

The following bug has been logged online:

Bug reference:      5128
Logged by:
Email address:      landreville@deadtreepages.com
PostgreSQL version: 8.4
Operating system:   FreeBSD
Description:        Returning nested composite types in plpython
Details:

I have nested custom types and when I try to return a mapping in python the
nested type gives me a malform record error. Here is my test code and the
error:


create type type1 as (
    col1 text,
    col2 text
);

create type type2 as (
    col1 text,
    col2 text,
    test_type type1
);

create function returnComposite(test_one text, test_three text) RETURNS
type2 as
$$
    return {'col1': test_one, 'col2': test_one, 'test_type': {'col1': test_two,
'col2': test_two}}
$$ language plpythonu;

select returnComposite('test1','test2')

ERROR: malformed record literal: "{'col2': 'test2', 'col1': 'test2'}"
SQL state: 22P02
Detail: Missing left parenthesis.


If I put the nested type as ('test': test_two) it will return me the type
but it includes extra quotes. The only way to make this work is make a
select using plpy returning a type2 column.

It would seem that the nested composite type is not being processed by
plpython and going straight to the rowtypes processing.

On Tue, Oct 20, 2009 at 12:19 PM,  <landreville@deadtreepages.com> wrote:
>
> The following bug has been logged online:
>
> Bug reference: =A0 =A0 =A05128
> Logged by:
> Email address: =A0 =A0 =A0landreville@deadtreepages.com
> PostgreSQL version: 8.4
> Operating system: =A0 FreeBSD
> Description: =A0 =A0 =A0 =A0Returning nested composite types in plpython
> Details:
>
> I have nested custom types and when I try to return a mapping in python t=
he
> nested type gives me a malform record error. Here is my test code and the
> error:
>
>
> create type type1 as (
> =A0 =A0 =A0 =A0col1 text,
> =A0 =A0 =A0 =A0col2 text
> );
>
> create type type2 as (
> =A0 =A0 =A0 =A0col1 text,
> =A0 =A0 =A0 =A0col2 text,
> =A0 =A0 =A0 =A0test_type type1
> );
>
> create function returnComposite(test_one text, test_three text) RETURNS
> type2 as
> $$
> =A0 =A0 =A0 =A0return {'col1': test_one, 'col2': test_one, 'test_type': {=
'col1': test_two,
> 'col2': test_two}}
> $$ language plpythonu;
>
> select returnComposite('test1','test2')
>
> ERROR: malformed record literal: "{'col2': 'test2', 'col1': 'test2'}"
> SQL state: 22P02
> Detail: Missing left parenthesis.
>
>
> If I put the nested type as ('test': test_two) it will return me the type
> but it includes extra quotes. The only way to make this work is make a
> select using plpy returning a type2 column.
>
> It would seem that the nested composite type is not being processed by
> plpython and going straight to the rowtypes processing.

See Peter's note here - apparently this is not supported.

http://archives.postgresql.org/pgsql-bugs/2009-11/msg00073.php

...Robert