Materialized views should be in a separate tablespace from the base table.
For partitioned tables and indexes, each partition should be in its own tablespace.
Using EM Database Control, you can identify overall contention on any tablespace by
identifying hotspots, either at the file level or at the object level. We??™ll cover performance
tuning, including resolving I/O contention issues, in Chapter 8.
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CHAPTER
4
Physical Database Layouts
and Storage Management
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76 Oracle Database 11g DBA Handbook
n Chapter 3, we talked about the logical components of the database, tablespaces,
and how to not only create the right number and types of tablespaces but also to
place table and index segments in the appropriate tablespace, based on their usage
patterns and function. In this chapter, I??™ll focus more on the physical aspects of a
database, the datafiles, and where to store them to maximize I/O throughput and
overall database performance.
The assumption throughout this chapter is that you are using locally managed tablespaces
with automatic segment space management. In addition to reducing the load on the SYSTEM
tablespace by using bitmaps stored in the tablespace itself instead of freelists stored in the table
or index header blocks, automatic segment space management (autoallocated or uniform) makes
more efficient use of the space in the tablespace. As of Oracle 10g, the SYSTEM tablespace is
created as locally managed.
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