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Posted to commits@impala.apache.org by ta...@apache.org on 2019/05/29 15:34:03 UTC
[impala] 07/07: IMPALA-7186: [DOCS] Documented the KUDU_READ_MODE
query option
This is an automated email from the ASF dual-hosted git repository.
tarmstrong pushed a commit to branch 2.x
in repository https://gitbox.apache.org/repos/asf/impala.git
commit 2413c6c0b5a78ca4e8d918319f9986fa75eec66b
Author: Alex Rodoni <ar...@cloudera.com>
AuthorDate: Mon Jul 9 19:42:03 2018 -0700
IMPALA-7186: [DOCS] Documented the KUDU_READ_MODE query option
Change-Id: I49b4ec29ae8cdbee8b3d38bdf2e678b4e9560952
Reviewed-on: http://gerrit.cloudera.org:8080/10897
Reviewed-by: Alex Rodoni <ar...@cloudera.com>
Tested-by: Impala Public Jenkins <im...@cloudera.com>
Reviewed-on: http://gerrit.cloudera.org:8080/13455
---
docs/impala.ditamap | 1 +
docs/impala_keydefs.ditamap | 4 +-
docs/topics/impala_kudu_read_mode.xml | 88 +++++++++++++++++++++++++++++++++++
3 files changed, 92 insertions(+), 1 deletion(-)
diff --git a/docs/impala.ditamap b/docs/impala.ditamap
index 228da2e..8872fa1 100644
--- a/docs/impala.ditamap
+++ b/docs/impala.ditamap
@@ -195,6 +195,7 @@ under the License.
<topicref href="topics/impala_explain_level.xml"/>
<topicref href="topics/impala_hbase_cache_blocks.xml"/>
<topicref href="topics/impala_hbase_caching.xml"/>
+ <topicref href="topics/impala_kudu_read_mode.xml"/>
<topicref href="topics/impala_live_progress.xml"/>
<topicref href="topics/impala_live_summary.xml"/>
<topicref href="topics/impala_max_errors.xml"/>
diff --git a/docs/impala_keydefs.ditamap b/docs/impala_keydefs.ditamap
index 9cce199..b216f02 100644
--- a/docs/impala_keydefs.ditamap
+++ b/docs/impala_keydefs.ditamap
@@ -10521,6 +10521,7 @@ under the License.
<keydef href="https://issues.apache.org/jira/browse/IMPALA-9999" scope="external" format="html" keys="IMPALA-9999"/>
<!-- Short form of mapping from Impala release to vendor-specific releases, for use in headings. -->
+ <keydef keys="impala31"><topicmeta><keywords><keyword>Impala 3.1</keyword></keywords></topicmeta></keydef>
<keydef keys="impala30"><topicmeta><keywords><keyword>Impala 3.0</keyword></keywords></topicmeta></keydef>
<keydef keys="impala212"><topicmeta><keywords><keyword>Impala 2.12</keyword></keywords></topicmeta></keydef>
<keydef keys="impala211"><topicmeta><keywords><keyword>Impala 2.11</keyword></keywords></topicmeta></keydef>
@@ -10540,6 +10541,7 @@ under the License.
<!-- 3-part forms of version numbers, for use in release notes. -->
<!-- Using spaced-out form to avoid conflict with variable for 2.1.10 -->
+ <keydef keys="impala3_1_0"><topicmeta><keywords><keyword>Impala 3.1.0</keyword></keywords></topicmeta></keydef>
<keydef keys="impala3_00_0"><topicmeta><keywords><keyword>Impala 3.0.0</keyword></keywords></topicmeta></keydef>
<keydef keys="impala2_12_0"><topicmeta><keywords><keyword>Impala 2.12.0</keyword></keywords></topicmeta></keydef>
<keydef keys="impala2_11_0"><topicmeta><keywords><keyword>Impala 2.11.0</keyword></keywords></topicmeta></keydef>
@@ -10581,7 +10583,7 @@ under the License.
<keydef keys="impala132"><topicmeta><keywords><keyword>Impala 1.3.2</keyword></keywords></topicmeta></keydef>
<keydef keys="impala130"><topicmeta><keywords><keyword>Impala 1.3.0</keyword></keywords></topicmeta></keydef>
-<!-- Long form of mapping from Impala release to vendor-specific releases, for use in running text. -->
+ <keydef keys="impala31_full"><topicmeta><keywords><keyword>Impala 3.1</keyword></keywords></topicmeta></keydef>
<keydef keys="impala30_full"><topicmeta><keywords><keyword>Impala 3.0</keyword></keywords></topicmeta></keydef>
<keydef keys="impala213_full"><topicmeta><keywords><keyword>Impala 2.13</keyword></keywords></topicmeta></keydef>
<keydef keys="impala212_full"><topicmeta><keywords><keyword>Impala 2.12</keyword></keywords></topicmeta></keydef>
diff --git a/docs/topics/impala_kudu_read_mode.xml b/docs/topics/impala_kudu_read_mode.xml
new file mode 100644
index 0000000..a2d34b0
--- /dev/null
+++ b/docs/topics/impala_kudu_read_mode.xml
@@ -0,0 +1,88 @@
+<?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="kudu_read_mode" rev="3.1.0 IMPALA-6812">
+
+ <title>KUDU_READ_MODE Query Option (<keyword keyref="impala31"/> or higher only)</title>
+
+ <titlealts audience="PDF">
+
+ <navtitle>KUDU_READ_MODE</navtitle>
+
+ </titlealts>
+
+ <prolog>
+ <metadata>
+ <data name="Category" value="Impala"/>
+ <data name="Category" value="Impala Query Options"/>
+ <data name="Category" value="Performance"/>
+ <data name="Category" value="Developers"/>
+ <data name="Category" value="Data Analysts"/>
+ </metadata>
+ </prolog>
+
+ <conbody>
+
+ <p rev="3.1.0 IMPALA-6812">
+ The <codeph>KUDU_READ_MODE</codeph> query option allows you to set a desired consistency
+ level for scans of Kudu tables.
+ </p>
+
+ <p>
+ <b>Type:</b> String
+ </p>
+
+ <p>
+ <b>Default:</b> <codeph>"DEFAULT"</codeph>
+ </p>
+
+ <p>
+ <b>Added in:</b> <keyword keyref="impala31"/>
+ </p>
+
+ <p conref="../shared/impala_common.xml#common/usage_notes_blurb"/>
+
+ <p>
+ The following values are supported for the query option:
+ <ul>
+ <li>
+ <codeph>"DEFAULT"</codeph>: The value of the startup flag,
+ <codeph>--kudu_read_mode</codeph>, is used.
+ </li>
+
+ <li>
+ <codeph>"READ_LATEST"</codeph>: Commonly known as the Read Committed isolation mode,
+ in this mode, Kudu provides no consistency guarantees for this mode, except that all
+ returned rows were committed at some point.
+ </li>
+
+ <li>
+ <codeph>"READ_AT_SNAPSHOT"</codeph>: Kudu will take a snapshot of the current state of
+ the data and perform the scan over the snapshot, possibly after briefly waiting for
+ ongoing writes to complete. This provides "Read Your Writes" consistency within a
+ single Impala session, except in the case of a Kudu leader change. See the Kudu
+ documentation for more details.
+ </li>
+ </ul>
+ </p>
+
+ </conbody>
+
+</concept>