how to check if oracle database is encrypted

Database encryption is a important concept these days because of security breaches . It is common practice to have database encryption enabled in Oracle database. Encryption can be present at two Level

TDE ( Transparent Data encryption) : This is setup for Table level
TSE (Tablespace encryption): This is setup for Tablespace level

Here is how to check if oracle database is encrypted

To check the wallet or Keystore in Oracle database

select WRL_PARAMETER, status, WALLET_TYPE from v$encryption_wallet;

To check the Master key in the Wallet

SELECT * FROM V$ENCRYPTION_KEYS;

To check for encrypted column in the tables

SET LINESIZE 100
COLUMN owner FORMAT A10
COLUMN table_name FORMAT A20
COLUMN column_name FORMAT A20
SELECT * FROM dba_encrypted_columns;

To check the tablespace level encryption in Oracle database

SELECT NAME, ENCRYPTIONALG, ENCRYPTEDTS
FROM V$ENCRYPTED_TABLESPACES, V$TABLESPACE
WHERE V$ENCRYPTED_TABLESPACES.TS# = V$TABLESPACE.TS#;

To check if particular Tablespace is encrypted

SELECT tablespace_name, encrypted, status FROM dba_tablespaces where tablespace_name = "&tablespace_name"

Following are Encrypted Algorithm existing with Oracle Database

AES192: Sets the key length to 192 bits. AES is the abbreviation for Advanced Encryption Standard.
3DES168: Sets the key length to 168 bits. 3DES is the abbreviation for Triple Data Encryption Standard.
AES128: Sets the key length to 128 bits. This option is the default.
AES256: Sets the key length to 256 bits.