ActiveRecord::StatementInvalid: PG::CharacterNotInRepertoire: ERROR: invalid byte sequence for encoding "UTF8": 0x92 about postgres-copy

[diogob]

You should set the client_encoding in the PostgreSQL connection.
I believe you can set this in the options when you open the connection (should be in database.yml in rails apps).

But if your database is in UTF-8 then this won't work (because PostgreSQL will still try to read your data and convert to the DB encoding) and the best approach will be to clean the file and get rid of invalid UTF-8 byte sequences.