Harald Krake <harald(at)krake(dot)de> writes:
> But now I'm wondering whether there are any good reasons
> not to type cast by default?
This has been suggested, and rejected, repeatedly. It's not a good
idea to apply a driver-side band-aid to mask a server-side problem;
especially not when the driver does not have adequate information to
fix the problem properly. (In other words, any driver-side solution
will fix some queries and break others.)
There will be a real solution in the backend someday soon, perhaps 7.4.
regards, tom lane