I was reviewing some features in Oracle and, basically, every single time I review them I find something new. Seems Oracle Databases’ features are near to infinite and we frequently find some that can really add value to our solutions.
So I decided to make a serie of posts with really quick notes about each one of them.
You can see all posts in this serie in my page of posts and some others more.
Ready? Here it goes:
Oracle SecureFiles | In 11.2 extended to Oracle Database File System – DBFS
In version 11g Oracle introduced SecureFiles, a new LOB storage architecture as replacement for BASICFILES LOBs’storage, being faster than Unix files to read/write. Lots of potential benefits for OLAP analytic workspaces are expected, as the LOBs used to hold AWs have historically been very slow to write. In addition, this object type is compliant to other mechanisms like deduplication, compression and encryption. Besides that, lock and concurrency model has been improved to manage those kind of objects. Other improvements like space management, reduced fragmentation, intelligent pre-fetching, new network layer, no LOB index contention, no high water mark contention and being easier to manage are important to mention.
The conversion from pre-11g storage architecture to SecureFile can be done using CTAS/ITAS, online redefinition, export/import, column to column copy, or using a view and a new column. Recommended a detailed review in referred documents for that, once specific adjustments as parallel DML can be used.
In 11g Release 2 this concept was extended: All files in the database can be transparently accessed using any operating system (OS) program that acts on files. For example, ETL (Extract, Transform and Load) tools can transparently store staging files in the database. The Oracle Database File System (DBFS) creates a standard file system interface on top of files and directories that are stored in database tables. DBFS is similar to NFS in that it provides a shared network file system that looks like a local file system. Like NFS, there is a server component and a client component.
The DBFS Content API is the PL/SQL interface in the Oracle RDBMS that lies at the core of DBFS. It includes a programmatic interface that allows different types of storage to be supported, including user-defined storage. The DBFS SecureFiles Store is a DBFS Content Store that utilizes a table with a SecureFiles LOB column to store the file system data. It implements POSIX-like capabilities.
This is a complex and extensive subject. I’ve gave you just a high level idea. If this subject is important for you, please follow the official documentation in docs.oracle.com.