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| <!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> |