I've been handed a database and asked whether any of it is encrypted. How to tell? There's TDE, obfuscation toolkit, - is there anyway to encrypt the entire database? Is there anyway to tell whether encryption is being used just being handed a database and asked the question - is any of it encrypted?
there is tablespace encryption
select tablespace_name, encrypted from dba_tablespaces;
there is column encryption
select * from dba_encrypted_columns
http://docs.oracle.com/cd/E18283_01/server.112/e17110/statviews_3168.htm there is lob (securefile) encryption
select * from dba_lobs.encrypt
http://docs.oracle.com/cd/E11882_01/server.112/e40402/statviews_4110.htm then there is application encryption which could be done a) in the application b) using dbms_obfuscation_toolkit or c) the dbms_crypto package.
You can use dba_dependencies to see if anything is dependent on dbms_obfuscation_toolkit or dbms_crypto, that would give an a clue that something could be encrypted (but cannot be conclusively used to prove NOTHING is encrypted).
You can look for RAW or LONG RAW or BLOB columns - those are the only columns suitable for encrypted data.
but you cannot conclusively determine if application encrypted data exists or not - there is nothing special about it to us other than the application should be using a binary datatype to store it.