Re: Rows from a stored procedure result are stringified

On 12/21/2011 03:14 PM, Daniele Varrazzo wrote:
>> I would expect the rows to come back from cursor.fetchall() in this
>> structure:
>>
>> [(1,2),(3,4),(5,6)]
>>
>> But they are returned like this:
>>
>> [('(1,2)'),('(3,4)'),('(5,6)')]
>>
>> This makes no sense to me.  Is this expected/documented behavior?
>
> Yes: it is expected: if psycopg finds a type it doesn't know, it will
> just return the string passed by the database. Doesn't it make sense? :-)
>
> You can extend psycopg adding your custom type using
> register_composite(): see <
> http://initd.org/psycopg/docs/extras.html#composite-types-casting>. It
> requires psycopg 2.4 though. Alternatively you can write and register
> your own type parser: see
> <http://initd.org/psycopg/docs/advanced.html#type-casting-of-sql-types-into-python-objects>.

Hmm.  This makes sense to some degree.  I do note that strings coming
back from the database are not quoted.  Is there a parsing routine in
psycopg that I can leverage to turn this kind of database-provided
tuple-as-a-string representation into a proper tuple/list?

--
Chris Howie
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