Oracle Degree of Parallelism
Oracle Degree of Parallelism
Oracle can parallelize operations that demand processing an total table or an entire partition. These operations include, The Parallel query is the most ordinarily utilize of Oracle’s parallel execution features. The Parallel execution can importantly reduce the elapsed time for large queries, but it doesn’t apply to every query. Oracle parallel query allows you to control the number of parallel query slave procedure that service a table with the DEGREE clause.
The Oracle states that the optimal degree of parallelism for a query is based on various factors. These factors are introduced in their order of importance:
The number of CPUs on the server
The number of physical disks that the table resides upon
For parallelizing by partition, the number of partitions that will be accessed, based upon partition pruning
For parallel DML procedure with global index maintenance, the minimum number of transaction freelists amongst all the global indexes to be updated.