Changes in the behavior of the connectby function in PostgreSQL 9.5 have prompted its removal from the database. It is easier for Evergreen to maintain compatibility with previous versions of PostgreSQL without this function.

By eliminating the use of the connectby function, we eliminate the requirement for the tablefunc database extension. It is no longer installed when the database is created. If you are upgrading and wish to remove it from your database, you may run the following statement in the database to drop it:

DROP EXTENSION tablefunc;