During the day, most OLTP systems should probably not use parallel execution.During off-hours, however, parallel execution can effectively process high-volume batch operations.For example, a bank might use parallelized batch programs to perform millions of updates to apply interest to accounts.
When executing a parallel operation, the parallel execution coordinator obtains parallel execution servers from the pool and assigns them to the operation.
If necessary, Oracle can create additional parallel execution servers for the operation.
These parallel execution servers remain with the operation throughout job execution, then become available for other operations.
Parallel execution dramatically reduces response time for data-intensive operations on large databases typically associated with decision support systems (DSS) and data warehouses.
You can also implement parallel execution on certain types of online transaction processing (OLTP) and hybrid systems.
Parallel execution improves processing for: You can also use parallel execution to access object types within an Oracle database.
For example, you can use parallel execution to access large objects (LOBs).
Parallel execution benefits systems with all of the following characteristics: If your system lacks any of these characteristics, parallel execution might not significantly improve performance.
In fact, parallel execution may reduce system performance on overutilized systems or systems with small I/O bandwidth.