Is there a theory or key for determining the degree of parallelism in an Oracle query? For instance:
select * from some_table;
If I want to run it in parallel, I can write it as shown below, which sets the parallel power to 10:
select /*+parallel(10) */ * from some_table;
the degree number can be changed to any other number. If you check the explanation plan, you will find that the higher the degree of parallelism, the lower the cost. My question is how to find the optimal degree number when you write a query, and is there a theory or key to determine the degree of parallelism in an Oracle query?
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