Solution to Unsupported startup parameter extra float digits Error

If you receive the ERROR: Unsupported startup parameter: extra_float_digits error during the PostgreSQL connection and you are using pgbouncer, 

the reason for the error is due to the lack of extra_float_digits in the ignore_startup_parameters parameter.

For the solution, follow the commands below one by one.

pgbouncer.ini

ignore_startup_parameters = application_name extra_float_digits