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Chapter 16: Managing Large Databases 545
Creating Tablespaces in a VLDB Environment
The considerations for creating tablespaces in a small database (terabyte range or smaller) also
apply to VLDBs: Spread out I/O across multiple devices, use a logical volume manager (LVM)
with RAID capabilities, or use ASM. In this section, I will present more detail and examples for
bigfile tablespaces. Because a bigfile tablespace contains only one datafile, the ROWID format
for objects stored in a bigfile tablespace is different, allowing for a tablespace size as large as
eight million terabytes, depending on the tablespace??™s block size.
Bigfile tablespaces are best suited for an environment that uses ASM, Oracle-Managed Files
(OMF), and Recovery Manager (RMAN) with a flash recovery area. See Chapter 4 for a detailed
review of ASM; Chapter 12 presents RMAN from a command-line and EM Database Control
perspective and leverages the flash recovery area for all backups. Finally, Chapter 6 describes
OMF from a space-management perspective.
In the next few sections, I will present an in-depth look at creating a bigfile tablespace and
specifying its characteristics; in addition, we will discuss the impact of bigfile tablespaces on both
initialization parameters and data dictionary views. Finally, I will show you how the dbverify utility
has been revised in Oracle 10g to allow you to analyze a single bigfile datafile using parallel
processes.
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