
12.4
Demonstrating Parallel Execution 339
Chapter 12
12.4 Demonstrating Parallel Execution
This section will cover different aspects of parallel execution, including paral-
lel queries, indexing, subqueries, DML, and, finally, partitioning operations.
12.4.1 Parallel Queries
First, let’s show a query plan for a serially executed query, as shown in Fig-
ure 12.2.
There are two ways to execute queries against tables in parallel. The first
involves the PARALLEL hint and the second involves the CREATE
TABLE or ALTER TABLE statements, including the parallel clause. Figure
12.3 shows an example parallel execution.
When attempting to persuade the optimizer ...