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<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="parquet_fallback_schema_resolution" rev="2.6.0 IMPALA-2835">
<title>PARQUET_FALLBACK_SCHEMA_RESOLUTION Query Option (<keyword keyref="impala26"/> or higher only)</title>
<titlealts audience="PDF"><navtitle>PARQUET FALLBACK SCHEMA RESOLUTION</navtitle></titlealts>
<prolog>
<metadata>
<data name="Category" value="Impala"/>
<data name="Category" value="Impala Query Options"/>
<data name="Category" value="Parquet"/>
<data name="Category" value="Schemas"/>
<data name="Category" value="Developers"/>
<data name="Category" value="Data Analysts"/>
</metadata>
</prolog>
<conbody>
<p rev="2.6.0 IMPALA-2835">
<indexterm audience="hidden">PARQUET_FALLBACK_SCHEMA_RESOLUTION query option</indexterm>
The <codeph>PARQUET_FALLBACK_SCHEMA_RESOLUTION</codeph> query option allows Impala to look
up columns within Parquet files by column name, rather than column order,
when necessary.
The allowed values are:
<ul>
<li>
POSITION (0)
</li>
<li>
NAME (1)
</li>
</ul>
</p>
<p conref="../shared/impala_common.xml#common/usage_notes_blurb"/>
<p>
By default, Impala looks up columns within a Parquet file based on
the order of columns in the table.
The <codeph>name</codeph> setting for this option enables behavior for
Impala queries similar to the Hive setting <codeph>parquet.column.index access=false</codeph>.
It also allows Impala to query Parquet files created by Hive with the
<codeph>parquet.column.index.access=false</codeph> setting in effect.
</p>
<p>
<b>Type:</b> integer or string
</p>
<p conref="../shared/impala_common.xml#common/added_in_260"/>
<p conref="../shared/impala_common.xml#common/related_info"/>
<p>
<xref href="impala_parquet.xml#parquet_schema_evolution"/>
</p>
</conbody>
</concept>