Database Reference
In-Depth Information
SQL Plan
The Plan tab provides the actual explain plan for the SQL ID detailed, either in graphical or tabular format. The tabular
version, shown in Figure 9-18 , offers a drop-down menu if more than one hash plan value is available for the SQL
statement. Basic plan information is shown, such as the parsing schema, optimizer mode, source of the statement, and
capture time.
Figure 9-18. Tabular representation of an explain plan for a statement from the SQL Details page
Also provided in the EM12c console version of the tabular plan are the type of waits by legend color in the
Optimization Cost section. You can also see the rows, along with a graph line to quickly access the number of rows
expected to be returned, and the bytes, again displayed with a visual indicator of the number of bytes expected.
You can click any of the indicators in the Predicate column (highlighted in Figure 9-18 ) to view predicates and filters
and more-detailed information on the step in question.
The graphical version of the Plan tab in SQL Details provides a visual display of the explain plan (see Figure 9-19 ).
This is a step-by-step path of the statement, displaying joins, loops, and group objects through the SQL execution.
Figure 9-19. Graphical explain plan for a statement, demonstrating a merge join highlighted in the console pane
Projections, definitive column joins, and even bloom filters are shown when highlighting sections of the explain
plan's graphical format. The buttons at the upper right in Figure 9-19 enable you to change the display to a vertical
map from horizontal, perform a rewrite, or print out the explain plan graphic. The zoom bar on the left, under the
Graphical and Tabular radio buttons, enables you to zoom in and out as needed.
 
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