Does compression work with TDE?
Customers using TDE tablespace encryption get the full benefit of compression (standard and Advanced Compression, as well as Exadata Hybrid Columnar Compression (EHCC)) because compression is applied before the data blocks are encrypted. Customers using TDE column encryption will get the full benefit of compression only on table columns that are not encrypted. Individual table columns that are encrypted using TDE column encryption will have a much lower level of compression because the encryption takes place in the SQL layer before the advanced compression process.
