I am curious about the MongoDB factory

environment
java -17
spring boot

I have set up a yml file to use mongodb. and
I thought that the DB connection was not possible because the setting information was incorrect.

However, I connected to MongoDB in my local area, not MongoDB in the external computer.
I did not provide any access information. (exclude incorrect information)
However, as a result of query execution, I connected to the database called test in mongo on the local pc.

I did some debugging and the mongofactory was giving the database name as test.
but couldn’t find any more info

Question: Is the DB connection information called test set in the local pc as the mongo factory default setting?