Versions 2 of the BI Connector uses the MySQL wire protocol, as opposed the Postgres protocol used in version 1. Users familiar or migrating from version 1 on the BI Connector often expect that mongosqld acts as a proxy for Postgres and expect to connect with a Postgres database driver. Our release notes and a FAQ need to be updated to make this change very clear.

Please make not of this change in
release notes
and
FAQs