Chapter 48

Determining the Table Rebuild Ratio for Oracle Tables

Roman Kab

Today’s Oracle DBA is armed with sophisticated monitoring and analysis tools to alleviate the complexity of managing state-of-the-art Oracle systems. Many third-party tools offer automated table–index defragmentation based on prebuild thresholds, while some simply identify potential objects. But many experienced Oracle DBAs still prefer their own scripts and programs.

This chapter presents a technique to identify tables that will cause an Oracle database to consume unnecessary system resources during full-table scans. This is because Oracle will read all segment blocks below the highwater mark, regardless of the presence of data in these blocks. Appendix 48.1 provides ...

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