Database Reference
In-Depth Information
Figure 13.12
A Flashback
Versions Query
Including
Pseudocolumns.
[ { ENABLE | DISABLE } TRIGGERS ];
FLASHBACK DATABASE and FLASHBACK TABLE allow restore of
either the entire database or a single table back to—and in the case of a
table, even forward to—a different SCN.
The next step is to examine parallel queries.
13.4
Parallel Queries
In an ideal world, parallel queries are useful on multiple CPU platforms
when Oracle Partitioning is being used with separate disks or RAID arrays.
Generally, parallel queries are only an advantage for very large tables or in
very large databases such as data warehouses. Using parallel queries on
small, highly active concurrent OLTP databases can sometimes cause rather
