Oracle Database Discussions

I used below sql statement to create a table space:

CREATE TABLESPACE AAA DATAFILE BBB SIZE 10M AUTOEXTEND OFF ...

Notice, i did not give a full path instead just a file name, then query relevant tables to

get the full path of this data file, let's assume it is below path:

d:\oracle\...\BBB

So i do believe there is a default path that oracle can use it to create data file. My question

is how to get this default path before i create a table space.

Thanks a lot.