2011/1/23 Jan Urbański <wulczer@wulczer.org>:
> On 22/01/11 11:15, Hitoshi Harada wrote:
>> This is a review for https://commitfest.postgresql.org/action/patch_view?id=460
>
> Thanks,
>
>> One issue is typmod of record type.
>>
>> regression=# create or replace function func1(t text) returns record
>> as $$ return {'name': t, 'value': 0} $$ language plpythonu;
>> regression=# select * from func1('jan') as (name text, value bigint);
>> name | value
>> ------+-------
>> jan | 0
>> (1 row)
>>
>> regression=# select * from func1('jan') as (name text, value int);
>> ERROR: function return row and query-specified return row do not match
>> DETAIL: Returned type bigint at ordinal position 2, but query expects integer.
>
> That's a bug, thanks for spotting it.
>
>> It seems that typmod of PLyTypeInfo is not updated over statements
>> within the session. I saw the error doesn't occur when I re-connect to
>> the backend after the error.
>
> I tracked it down to caching the I/O functions for the return type. Your
> example shows that you can't just discover the output record type once,
> but you have to recheck whether the returned record's structure has not
> changed between calls.
>
> I implemented it by looping over the attributes of the output record and
> checking if type for which we have already cached the I/O function is
> binary coercible to the type that's actually in the record. This allows
> the code to skip recaching the functions in the common case when the
> record stays the same, and fixes the bug you found.
>
> Attached is a new patch for table function support and an incremental
> patch with the change I did. The new patch for table functions does not
> apply to HEAD, it's a refinement of the previous table-functions patch.
> After the refactor patches are all applied or rejected, I'll post a
> frech patch that applies cleanly to HEAD.
I tested the new incremental patch and the previous example works
fine. I don't know if this can be handled properly but another example
is:
regression=# create function func1(t text) returns record as $$ return
{'name':t, 'value':0}; $$ language plpythonu ;
CREATE FUNCTION
regression=# select * from func1('jan') as (name text, value bigint);name | value
------+-------jan | 0
(1 row)
regression=# select * from func1('jan') as (value text, name bigint);value | name
-------+------jan | 0
(1 row)
where value and name don't point to the correct data. Your
data-type-check logic might not be enough.
Regards,
--
Hitoshi Harada
