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eadd35f6d5
The recent documentation formatting changes introduced the navigation panel on the left. However, due to the length of the query options navigation title these could overlap with the documentation paragraphs. This commit removes the underscores from the navigation titles of the query options, so browsers can break them into multiple lines. Additionally, the "SET" and "Query Options for the SET Statement" pages are merged to save some more space for the query option navigation titles. Testing: - Built the documentation and tested manually Change-Id: Icec787d7a2af848aaaff65be2ecf311a5ce8fe7f Reviewed-on: http://gerrit.cloudera.org:8080/20556 Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com> Reviewed-by: Jason Fehr <jfehr@cloudera.com> Reviewed-by: Peter Rozsa <prozsa@cloudera.com> Reviewed-by: Tamas Mate <tmater@apache.org>
88 lines
2.8 KiB
XML
88 lines
2.8 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<!--
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Licensed to the Apache Software Foundation (ASF) under one
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or more contributor license agreements. See the NOTICE file
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distributed with this work for additional information
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regarding copyright ownership. The ASF licenses this file
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to you under the Apache License, Version 2.0 (the
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"License"); you may not use this file except in compliance
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with the License. You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing,
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software distributed under the License is distributed on an
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"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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KIND, either express or implied. See the License for the
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specific language governing permissions and limitations
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under the License.
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-->
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<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
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<concept id="kudu_read_mode" rev="3.1.0 IMPALA-6812">
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<title>KUDU_READ_MODE Query Option (<keyword keyref="impala31"/> or higher only)</title>
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<titlealts audience="PDF">
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<navtitle>KUDU READ MODE</navtitle>
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</titlealts>
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<prolog>
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<metadata>
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<data name="Category" value="Impala"/>
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<data name="Category" value="Impala Query Options"/>
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<data name="Category" value="Performance"/>
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<data name="Category" value="Developers"/>
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<data name="Category" value="Data Analysts"/>
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</metadata>
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</prolog>
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<conbody>
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<p rev="3.1.0 IMPALA-6812">
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The <codeph>KUDU_READ_MODE</codeph> query option allows you to set a desired consistency
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level for scans of Kudu tables.
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</p>
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<p>
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<b>Type:</b> String
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</p>
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<p>
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<b>Default:</b> <codeph>"DEFAULT"</codeph>
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</p>
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<p>
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<b>Added in:</b> <keyword keyref="impala31"/>
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</p>
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<p conref="../shared/impala_common.xml#common/usage_notes_blurb"/>
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<p>
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The following values are supported for the query option:
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<ul>
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<li>
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<codeph>"DEFAULT"</codeph>: The value of the startup flag,
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<codeph>‑‑kudu_read_mode</codeph>, is used. </li>
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<li>
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<codeph>"READ_LATEST"</codeph>: Commonly known as the Read Committed isolation mode,
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in this mode, Kudu provides no consistency guarantees for this mode, except that all
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returned rows were committed at some point.
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</li>
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<li>
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<codeph>"READ_AT_SNAPSHOT"</codeph>: Kudu will take a snapshot of the current state of
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the data and perform the scan over the snapshot, possibly after briefly waiting for
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ongoing writes to complete. This provides "Read Your Writes" consistency within a
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single Impala session, except in the case of a Kudu leader change. See the Kudu
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documentation for more details.
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</li>
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</ul>
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</p>
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</conbody>
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</concept>
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