Re: varchar vs char vs text

"Brett W. McCoy" <bmccoy@chapelperilous.net> writes:
> I'd go with text.  It's not SQL92, though.

Check.

> varchar is technically supposed to have a limit of 255,

Certainly not; the spec says

            The maximum value of <length> is implementation-defined.

There may be implementations that are lame enough to limit it to 255,
but Postgres isn't one of them.  IIRC, we set a rather arbitrary upper
limit of 10000000 on the length (mainly on the theory that anything
larger is either a typo, or you really don't want a limit at all, in
which case you oughta be using text).

At least in 7.2, it also works to say just "varchar" with no length
limit; this is functionally equivalent to "text" except perhaps for
some corner cases involving ambiguous-data-type resolution.  But
this is not SQL-spec-compliant either.

            regards, tom lane