Re: Confusion over Python drivers - Mailing list pgsql-hackers

From Jeff Davis
Subject Re: Confusion over Python drivers
Date
Msg-id 1265672065.29919.2466.camel@jdavis
Whole thread Raw
In response to Re: Confusion over Python drivers  (Andrew McNamara <andrewm@object-craft.com.au>)
Responses Re: Confusion over Python drivers  (Andrew McNamara <andrewm@object-craft.com.au>)
List pgsql-hackers
On Tue, 2010-02-09 at 09:15 +1100, Andrew McNamara wrote:
> I can't see how this would work with binary query parameters - the server
> will see a blob of binary data and have no way to know what it represents.

Unknown is unknown, whether in binary or text format. As far as I know,
PostgreSQL never looks inside a literal of unknown type to try to
determine its type -- it only looks at the context (to what function is
it an argument?).

For instance:
 SELECT '5'; -- has no idea what type it is
 SELECT '5' + 1; -- it's an int
 SELECT 'a' + 1; -- it's still an int ERROR:  invalid input syntax for integer: "a" LINE 1: SELECT 'a' + 1;
 SELECT '5.0' + 1; -- still an int, bad input format ERROR:  invalid input syntax for integer: "5.0" LINE 1: SELECT
'5.0'+ 1;
 

Regards,Jeff Davis



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