<li>Query plan <cmdname>Partition selector</cmdname> operator.</li>
<li>Query plan <cmdname>Split</cmdname> operator. </li>
</ul></li>
<li>When running <cmdname>EXPLAIN</cmdname>, the query plan generated by Pivotal Query
Optimizer is different than the plan generated by the legacy query optimizer.</li>
<li>When running <cmdname>EXPLAIN</cmdname>, the query plan generated by GPORCA is different than the plan generated by the legacy query optimizer.</li>
<li>Greenplum Database adds the log file message <codeph>Planner produced
plan</codeph> when GPORCA is enabled and Greenplum Database falls back to the legacy query optimizer to generate the query
server configuration parameter <cmdname>optimizer_control</cmdname>. For information about the
server configuration parameters, see the <cite>Greenplum Database Reference
Guide</cite>.</note>
<notetype="important">If you intend to execute queries on partitioned tables with the Pivotal
Query Optimizer enabled, you must collect statistics on the partitioned table root partition
<notetype="important">If you intend to execute queries on partitioned tables with GPORCA enabled, you must collect statistics on the partitioned table root partition
with the <cmdname>ANALYZE ROOTPARTITION</cmdname> command. The command <codeph>ANALYZE
ROOTPARTITION</codeph> collects statistics on the root partition of a partitioned table
based on the data in the table. Statistics are not collected on the leaf partitions, leaf
...
...
@@ -89,8 +88,7 @@
<p>You can use the <cmdname>SET</cmdname> command to set <cmdname>optimizer</cmdname> server
configuration parameter for a session. For example, after you use the
<cmdname>psql</cmdname> utility to connect to Greenplum Database, this
<cmdname>SET</cmdname> command enables the Pivotal Query
Optimizer:<codeblock>> set optimizer = on ;</codeblock></p>
<cmdname>SET</cmdname> command enables GPORCA:<codeblock>> set optimizer = on ;</codeblock></p>
<p>To set the parameter for a specific query, include the <cmdname>SET</cmdname> command prior
<shortdesc>There are limitations in Greenplum Database<ph>
4.3.5.0 and later</ph> when GPORCA is enabled. The Pivotal Query
Optimizer and the legacy query optimizer currently coexist in Greenplum Database<ph> 4.3.5.0 and later</ph> because GPORCA does not
4.3.5.0 and later</ph> when GPORCA is enabled. GPORCA and the legacy query optimizer currently coexist in Greenplum Database<ph> 4.3.5.0 and later</ph> because GPORCA does not
support all Greenplum Database features. </shortdesc>