Description of the illustration dwhsg017.eps
This figure illustrates how query rewrites works:
- 
                  First, you enter a query. 
- 
                  Then, Oracle generates the plan for your query. 
- 
                  Then, Oracle rewrites the statement. 
- 
                  Then, Oracle compares the cost of the two statements. 
- 
                  Oracle chooses the best result.