"PostgreSQL Bugs List" <pgsql-bugs(at)postgresql(dot)org> writes:
> the functions "lower()" and "upper()" do not seem to work correctly with
> ISO_8859_7 values
> CREATE DATABASE mediagrk WITH TEMPLATE = template0 ENCODING = 'ISO_8859_7';
upper/lower are driven by the database locale, not the encoding.
They are presently broken for multi-byte encodings, but I don't think
ISO_8859_7 is multi-byte.
regards, tom lane