As shown in Figure 16-12, on the Edit Table: OE.ORDER_QUOTE page you
select the Partitions tab and select the partition ORDER_QUOTE_P4 to change its characteristics.
When you select a partition (in this case, ORDER_QUOTE_P4) and click Advanced Options,
you have the ability to change the partition??™s characteristics as you would for a nonpartitioned
heap-based table. In Figure 16-13, you change the compression option for this partition only;
when rows are inserted during a direct path insert, the rows in this segment are compressed to save
space with only a slight increase in overhead to uncompress the rows when they are retrieved.
FIGURE 16-11 EM Database Control create partition confirmation
588 Oracle Database 11g DBA Handbook
FIGURE 16-12 OE.ORDER_QUOTE page
FIGURE 16-13 EM Database Control partition storage advanced options
Chapter 16: Managing Large Databases 589
Materialized Views
Another type of table, called a materialized view, shares the characteristics of a table and a view. It
is like a view in that it derives its results from a query against one or more tables; it is like a table in
that it persists the result set of a view in a segment. Materialized views are useful in both OLTP and
DSS systems. Frequent user queries against operational data may be able to use materialized views
instead of the repeated joining of many highly normalized tables, and in a data warehouse
environment the historical data can be aggregated ahead of time to make DSS queries run in a
fraction of the time it would take to aggregate the data ???on the fly.
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