Repository: impala Updated Branches: refs/heads/master e38715e25 -> df53ec238
IMPALA-7546: [DOCS] A new TIMEZONE query option Documented the new TIMEZONE query option to set a time TIMEZONE to be used in timestamp conversions. Change-Id: I734b8b37ae2360422fce269ed87507a04e8c05ac Reviewed-on: http://gerrit.cloudera.org:8080/11505 Tested-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Reviewed-by: Csaba Ringhofer <csringho...@cloudera.com> Project: http://git-wip-us.apache.org/repos/asf/impala/repo Commit: http://git-wip-us.apache.org/repos/asf/impala/commit/17bc980d Tree: http://git-wip-us.apache.org/repos/asf/impala/tree/17bc980d Diff: http://git-wip-us.apache.org/repos/asf/impala/diff/17bc980d Branch: refs/heads/master Commit: 17bc980d9540b29a1667841b7bffc2084204ac35 Parents: e38715e Author: Alex Rodoni <arod...@cloudera.com> Authored: Mon Sep 24 17:16:10 2018 -0700 Committer: Alex Rodoni <arod...@cloudera.com> Committed: Tue Sep 25 19:42:59 2018 +0000 ---------------------------------------------------------------------- docs/impala.ditamap | 1 + docs/topics/impala_timezone.xml | 119 +++++++++++++++++++++++++++++++++++ 2 files changed, 120 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/impala/blob/17bc980d/docs/impala.ditamap ---------------------------------------------------------------------- diff --git a/docs/impala.ditamap b/docs/impala.ditamap index ce88c01..213d2c9 100644 --- a/docs/impala.ditamap +++ b/docs/impala.ditamap @@ -235,6 +235,7 @@ under the License. <topicref href="topics/impala_sync_ddl.xml"/> <topicref href="topics/impala_thread_reservation_aggregate_limit.xml"/> <topicref href="topics/impala_thread_reservation_limit.xml"/> + <topicref href="topics/impala_timezone.xml"/> </topicref> </topicref> <topicref href="topics/impala_show.xml"/> http://git-wip-us.apache.org/repos/asf/impala/blob/17bc980d/docs/topics/impala_timezone.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_timezone.xml b/docs/topics/impala_timezone.xml new file mode 100644 index 0000000..ced9475 --- /dev/null +++ b/docs/topics/impala_timezone.xml @@ -0,0 +1,119 @@ +<?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 rev="3.1.0" id="timezone"> + + <title>TIMEZONE Query Option (<keyword keyref="impala31_full"/> or higher only)</title> + + <titlealts audience="PDF"> + + <navtitle>TIMEZONE</navtitle> + + </titlealts> + + <prolog> + <metadata> + <data name="Category" value="Impala"/> + <data name="Category" value="Impala Query Options"/> + <data name="Category" value="Querying"/> + <data name="Category" value="Developers"/> + <data name="Category" value="Data Analysts"/> + </metadata> + </prolog> + + <conbody> + + <p> + The <codeph>TIMEZONE</codeph> query option defines the timezone used for conversions + between UTC and the local time. If not set, Impala uses the system time zone where the + Coordinator Impalad runs. As query options are not sent to the Coordinator immediately, + the timezones are validated only when the query runs. + </p> + + <p> + Impala takes the timezone into a consideration in the following cases: + <ul> + <li> + When calling the <codeph>NOW()</codeph> function + </li> + + <li> + When converting between Unix time and timestamp if the + <codeph>use_local_tz_for_unix_timestamp_conversions</codeph> flag is + <codeph>TRUE</codeph> + </li> + + <li> + When reading Parquet timestamps written by Hive if the + <codeph>convert_legacy_hive_parquet_utc_timestamps</codeph> flag is + <codeph>TRUE</codeph> + </li> + </ul> + </p> + + <p> + <b>Syntax:</b> + </p> + +<codeblock>SET TIMEZONE=<varname>time zone</varname></codeblock> + + <p> + <varname>time zone</varname> can be a canonical code or a time zone name defined in + <xref + href="https://en.wikipedia.org/wiki/List_of_tz_database_time_zones"; + format="html" scope="external">IANA + Time Zone Database</xref>. The value is case-sensitive. + </p> + + <p> + Leading/trailing quotes (') and double quotes (") are stripped. + </p> + + <p> + If <varname>time zone</varname> is an empty string, the time zone for the query is set to + the default time zone of the Impalad Coordinator. + </p> + + <p> + If <varname>time zone</varname> is <codeph>NULL</codeph> or a space character, Impala + returns an error when the query is executed. + </p> + + <p> + <b>Type:</b> String + </p> + + <p> + <b>Default:</b> The system time zone where the Coordinator Impalad runs + </p> + + <p> + <b>Examples:</b> +<codeblock>SET TIMEZONE=UTC; +SET TIMEZONE="Europe/Budapest";</codeblock> + </p> + + <p> + <b>Added in:</b> <keyword keyref="impala31"/> + </p> + + </conbody> + +</concept>
