David Johnston <polobo@yahoo.com> writes:
> On Nov 17, 2012, at 20:43, John R Pierce <pierce@hogranch.com> wrote:
>> I think he meant a tiny tiny bit faster, primarily due to not having to validate the length.
> Maybe... But I would presume a "varchar with no limit" does not validate length...
There is overhead from the type system for varchar, whether or not it
has a length limit --- you'll get at least some RelabelType nodes in
expression trees, and those don't have zero cost to execute.
I'd generally recommend using "text" if you don't have any interest in
enforcing a specific length limit.
regards, tom lane
