better way?

[Pet]

On 11 Aug., 22:19, "Rami Chowdhury" <rami.chowdh... at gmail.com> wrote:
> Ah, my apologies, I must have been getting it confused with ON UPDATE  
> [things]. Thanks for correcting me.
>
> On Tue, 11 Aug 2009 13:10:03 -0700, Matthew Woodcraft  
>
> <matt... at woodcraft.me.uk> wrote:
> > "Rami Chowdhury" <rami.chowdh... at gmail.com> writes:
>
> >> IIRC Postgres has had ON DUPLICATE KEY UPDATE functionality longer than
> >> MySQL...
>
> > PostgreSQL does not have ON DUPLICATE KEY UPDATE.
>
> > The SQL standard way to do what the OP wants is MERGE. PostgreSQL
> > doesn't have that either.
>
> > -M-
>
> --
> Rami Chowdhury
> "Never attribute to malice that which can be attributed to stupidity" --  
> Hanlon's Razor
> 408-597-7068 (US) / 07875-841-046 (UK) / 0189-245544 (BD)

So, I'm doing it in right way?
What about building columns? map(lambda s: s + ' = %s', fields)
Is that o.k.?

thanks