rails/rails — pull request #14579 by senny (2014-04-03 13:02:54+00:00)
Title: PostgreSQL, remove varchar limit.

Closes #13435
Closes #9153

There is no reason for the PG adapter to have a default limit of 255 on :string
columns. See this snippet from the PG docs:

Tip: There is no performance difference among these three types, apart
from increased storage space when using the blank-padded type, and a
few extra CPU cycles to check the length when storing into a
length-constrained column. While character(n) has performance
advantages in some other database systems, there is no such advantage
in PostgreSQL; in fact character(n) is usually the slowest of the
three because of its additional storage costs. In most situations text
or character varying should be used instead.