Correct info about determining the optimizer being used
* Correct info on determining optimizer being used
* Update query-piv-opt-fallback.xml
Minor edit.
<p>You can examine the <codeph>EXPLAIN</codeph> query plan for the query determine which query
optimizer was used by Greenplum Database to execute the query:<ul
id="ul_vc2_xbh_1t">
- <li>When GPORCA generates the query plan, the setting
- <codeph>optimizer=on</codeph> and GPORCA version are displayed at
- the end of the query plan. For
- example.<codeblock> Settings: <b>optimizer=on</b>
- Optimizer status: <b>Pivotal Optimizer (GPORCA) version 1.584</b></codeblock><p>When
- Greenplum Database falls back to the Postgres Planner to generate the
- plan, the setting <codeph>optimizer=on</codeph> and <codeph>Postgres query
- optimizer</codeph> are displayed at the end of the query plan. For
- example.<codeblock> Settings: <b>optimizer=on</b>
- Optimizer status: <b>Postgres query optimizer</b></codeblock></p>When
- the server configuration parameter <codeph>OPTIMIZER</codeph> is <codeph>off</codeph>,
- these lines are displayed at the end of a query
- plan.<codeblock> Settings: <b>optimizer=off</b>
- Optimizer status: <b>Postgres query optimizer</b></codeblock></li>
+ <li>The optimizer is listed at the end of the query plan. For example, when GPORCA generates
+ the query plan, the query plan ends with:<codeblock> Optimizer: Pivotal Optimizer (GPORCA)</codeblock><p>When Greenplum
+ Database falls back to the Postgres Planner to generate the plan, the query plan
+ ends with:<codeblock> Optimizer: Postgres query optimizer</codeblock></p></li>
<li>These plan items appear only in the <codeph>EXPLAIN</codeph> plan output generated by
GPORCA. The items are not supported in a Postgres Planner query
plan.<ul id="ul_ej2_xbh_1t">
