We know Windows NTFS compression on Oracle Database datafiles is a bad idea.

See here and here.

It prevents Asynchronous Random Disk I/O which can increase the risk of corruption and generally slow down the database.

However, we have some Oracle databases (11g & 12c) on Windows Server 2012 R2 servers with Windows file compression on the datafiles. How do we safely deactivated this file compression? Are there any watch-outs?


  • 2
    I have done it on MSSQL. Just shut down the database service and uncompress the files.
    – paparazzo
    Commented Aug 12, 2016 at 15:56

1 Answer 1


As Paparazzi said for MSSQL, just shutdown the database and then decompress the files and startup again. If your architecture allows, you could offline a tablespace at a time and then just decompress the datafiles for that tablespace. Eventually though you will need do do the system tablespace and will need to shutdown the whole system.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.