What Are the Database Storage Options?

• Raw Devices, which enable management of storage devices outside the operating system with unformatted physical disk space. This is preferred for Oracle Real Application Clusters (RAC). This method is not explained in detail here as it is not widely used for general database applications. For more details, please refer to Oracle Documentation.
   

• Automatic Storage Management (ASM), which is a new functionality to define a pool of storage or disk group in which Oracle Database 10g automatically manages database file placements and naming. This option simplifies file management, database administration and improves performance in large environments. Automatic Storage Management requires a separate database instance to configure and manage disks. All disk management techniques like mirroring and striping are handled automatically by ASM.

For the installation reviewed in this chapter, the default selection of File System was chosen. The author recommends this method as ASM managed files can be added to the database at a later stage. Use ASM files only if comfortable with doing disk management commands as root or when help can be obtained to accomplish those tasks. Almost all companies are likely to have both File System managed and ASM managed files in their databases for a foreseeable future.

Using the ASM file method will be reviewed briefly in the DBCA section of this chapter and examined in more detail in Chapter 5. Figure 3.4 displays an image of the Storage Options screen with the File System option selected.

Figure 3.4 - Oracle Universal Installer – Storage Options