Issue #10673 has been updated by Sam Saffron.


pg gem have this fixed and plan to release a new stable version in a few more days. 

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Bug #10673: Ruby 2.2.0 bug in UTF-8 encoding with Postgres
https://bugs.ruby-lang.org/issues/10673#change-50685

* Author: Fred Guest
* Status: Third Party's Issue
* Priority: High
* Assignee: 
* Category: 
* Target version: 
* ruby -v: 2.2.0
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
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There is some kind of bug in Ruby 2.2.0 re UTF-8 encoding with Postgres. I upgraded a previously bug free Rails 4.1.5 app from Ruby 2.1.5 to Ruby 2.2.0 and started getting these errors "PG::CharacterNotInRepertoire: ERROR: invalid byte sequence for encoding UTF8" on user input email fields in both development and in a staging environment on Heroku. Downgrading to Ruby 2.1.5 with no other changes fixed the issue completely.



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