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Posted to commits@impala.apache.org by sa...@apache.org on 2018/04/23 17:38:50 UTC
[02/20] impala git commit: IMPALA-6867: [DOCS] SHUFFLE_DISTINCT_EXPRS
Query option added
IMPALA-6867: [DOCS] SHUFFLE_DISTINCT_EXPRS Query option added
Change-Id: I42cb22a13b26bdc3d22585e4fc23934dfc91722a
Reviewed-on: http://gerrit.cloudera.org:8080/10094
Reviewed-by: Tianyi Wang <tw...@cloudera.com>
Tested-by: Impala Public Jenkins <im...@cloudera.com>
Project: http://git-wip-us.apache.org/repos/asf/impala/repo
Commit: http://git-wip-us.apache.org/repos/asf/impala/commit/27d6f5ee
Tree: http://git-wip-us.apache.org/repos/asf/impala/tree/27d6f5ee
Diff: http://git-wip-us.apache.org/repos/asf/impala/diff/27d6f5ee
Branch: refs/heads/2.x
Commit: 27d6f5ee612d8abf84956529efffaaab183fd18b
Parents: a71f50a
Author: Alex Rodoni <ar...@cloudera.com>
Authored: Tue Apr 17 20:04:39 2018 -0700
Committer: Impala Public Jenkins <im...@gerrit.cloudera.org>
Committed: Thu Apr 19 22:10:20 2018 +0000
----------------------------------------------------------------------
docs/impala.ditamap | 1 +
docs/impala_keydefs.ditamap | 1 +
docs/topics/impala_shuffle_distinct_exprs.xml | 59 ++++++++++++++++++++++
3 files changed, 61 insertions(+)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/impala/blob/27d6f5ee/docs/impala.ditamap
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diff --git a/docs/impala.ditamap b/docs/impala.ditamap
index 8dd22f7..7ef7d47 100644
--- a/docs/impala.ditamap
+++ b/docs/impala.ditamap
@@ -226,6 +226,7 @@ under the License.
<topicref rev="2.8.0 IMPALA-3671" href="topics/impala_scratch_limit.xml"/>
<!-- This option is for internal use only and might go away without ever being documented. -->
<!-- <topicref href="topics/impala_seq_compression_mode.xml"/> -->
+ <topicref href="topics/impala_shuffle_distinct_exprs.xml"/>
<topicref href="topics/impala_support_start_over.xml"/>
<topicref href="topics/impala_sync_ddl.xml"/>
<topicref href="topics/impala_v_cpu_cores.xml"/>
http://git-wip-us.apache.org/repos/asf/impala/blob/27d6f5ee/docs/impala_keydefs.ditamap
----------------------------------------------------------------------
diff --git a/docs/impala_keydefs.ditamap b/docs/impala_keydefs.ditamap
index ae6b2f8..27f0515 100644
--- a/docs/impala_keydefs.ditamap
+++ b/docs/impala_keydefs.ditamap
@@ -10824,6 +10824,7 @@ under the License.
<keydef href="topics/impala_s3_skip_insert_staging.xml" keys="s3_skip_insert_staging"/>
<keydef href="topics/impala_scan_node_codegen_threshold.xml" keys="scan_node_codegen_threshold"/>
<keydef href="topics/impala_scratch_limit.xml" keys="scratch_limit"/>
+ <keydef href="topics/impala_shuffle_distinct_exprs.xml" keys="shuffle_distinct_exprs"/>
<keydef href="topics/impala_support_start_over.xml" keys="support_start_over"/>
<keydef href="topics/impala_sync_ddl.xml" keys="sync_ddl"/>
<keydef href="topics/impala_v_cpu_cores.xml" keys="v_cpu_cores"/>
http://git-wip-us.apache.org/repos/asf/impala/blob/27d6f5ee/docs/topics/impala_shuffle_distinct_exprs.xml
----------------------------------------------------------------------
diff --git a/docs/topics/impala_shuffle_distinct_exprs.xml b/docs/topics/impala_shuffle_distinct_exprs.xml
new file mode 100644
index 0000000..804ca4f
--- /dev/null
+++ b/docs/topics/impala_shuffle_distinct_exprs.xml
@@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept id="shuffle_distinct_exprs">
+
+ <title>SHUFFLE_DISTINCT_EXPRS Query Option</title>
+
+ <titlealts audience="PDF">
+
+ <navtitle>SHUFFLE_DISTINCT_EXPRS</navtitle>
+
+ </titlealts>
+
+ <prolog>
+ <metadata>
+ <data name="Category" value="Impala"/>
+ <data name="Category" value="Impala Query Options"/>
+ </metadata>
+ </prolog>
+
+ <conbody>
+
+ <p>
+ The <codeph>SHUFFLE_DISTINCT_EXPRS</codeph> query option controls the
+ shuffling behavior when a query has both grouping and distinct expressions.
+ Impala can optionally include the distinct expressions in the hash exchange
+ to spread the data among more nodes. However, this plan requires one more
+ hash exchange phase.
+ </p>
+
+ <p>
+ It is recommended that you turn off this option if the NDVs of the grouping
+ expressions are high.
+ </p>
+
+ <p conref="../shared/impala_common.xml#common/type_boolean"/>
+
+ <p conref="../shared/impala_common.xml#common/default_false"/>
+
+ </conbody>
+
+</concept>