On Sun, Feb 27, 2011 at 1:13 PM, Daniele Varrazzo <daniele.varrazzo@xxxxxxxxx> wrote: > Hello, > > I'm thinking about adding support for PQexecParams and PQprepare in > Psycopg. I've posted more details yesterday on the Psycopg mailing > list <http://archives.postgresql.org/psycopg/2011-02/msg00076.php>. I > have a few preliminary questions: If you are wrapping libpq, there really is no good reason not to use the parametrized interfaces exclusively...not doing that is just asking for SQL injection type problems. > How stable is the binary representation for the PostgreSQL types? We > may just pass bytea data in binary format and pass everything else as > text parameters, or pass different types too as binary, if performace > would benefit. Did binary format ever changed in the past (at least > since the introduction of the V3 protocol)? Is such binary > representation more likely to change in the future respect to the > textual one, in a way that forward/backward compatibility between > server and client would be compromised? The binary representations of types are mostly stable. On average of about one per release you might see a wire format change...it doesn't happen that often but you have to be prepared to deal with it. 'money' type is one example -- it was moved from 32 to 64 bit..there are a couple of others. Backwards compatibility is no problem but forwards compatibility is going to be problematic because you have no support from the server. In practice, it usually works ok. > Query plans for prepared statements may be less efficient than ones > for queries with bound parameters. Are query plans generated for > PQexecParams calls as efficient as the ones generated for PQexec? Or > do they have the same limitation of the ones generated for PQprepare? Query plans for PQexec is the same for PQexecParams. PQexec can be a tiny bit more efficient for simple queries but is not worth the risk unless you are sending 0 parameters. merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
