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These are refugees from doc_prototype. They can be rendered with the DITA Open Toolkit version 2.3.3 by: /tmp/dita-ot-2.3.3/bin/dita \ -i impala.ditamap \ -f html5 \ -o $(mktemp -d) \ -filter impala_html.ditaval Change-Id: I8861e99adc446f659a04463ca78c79200669484f Reviewed-on: http://gerrit.cloudera.org:8080/5014 Reviewed-by: John Russell <jrussell@cloudera.com> Tested-by: John Russell <jrussell@cloudera.com>
75 lines
2.9 KiB
XML
75 lines
2.9 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
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<concept id="langref">
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<title>Impala SQL Language Reference</title>
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<titlealts audience="PDF"><navtitle>SQL Reference</navtitle></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="SQL"/>
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<data name="Category" value="Data Analysts"/>
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<data name="Category" value="Developers"/>
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<data name="Category" value="impala-shell"/>
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</metadata>
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</prolog>
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<conbody>
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<p>
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Impala uses SQL as its query language. To protect user investment in skills development and query
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design, Impala provides a high degree of compatibility with the Hive Query Language (HiveQL):
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</p>
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<ul>
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<li>
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Because Impala uses the same metadata store as Hive to record information about table structure and
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properties, Impala can access tables defined through the native Impala <codeph>CREATE TABLE</codeph>
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command, or tables created using the Hive data definition language (DDL).
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</li>
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<li>
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Impala supports data manipulation (DML) statements similar to the DML component of HiveQL.
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</li>
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<li>
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Impala provides many <xref href="impala_functions.xml#builtins">built-in functions</xref> with the same
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names and parameter types as their HiveQL equivalents.
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</li>
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</ul>
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<p>
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Impala supports most of the same <xref href="impala_langref_sql.xml#langref_sql">statements and
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clauses</xref> as HiveQL, including, but not limited to <codeph>JOIN</codeph>, <codeph>AGGREGATE</codeph>,
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<codeph>DISTINCT</codeph>, <codeph>UNION ALL</codeph>, <codeph>ORDER BY</codeph>, <codeph>LIMIT</codeph> and
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(uncorrelated) subquery in the <codeph>FROM</codeph> clause. Impala also supports <codeph>INSERT
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INTO</codeph> and <codeph>INSERT OVERWRITE</codeph>.
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</p>
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<p>
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Impala supports data types with the same names and semantics as the equivalent Hive data types:
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<codeph>STRING</codeph>, <codeph>TINYINT</codeph>, <codeph>SMALLINT</codeph>, <codeph>INT</codeph>,
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<codeph>BIGINT</codeph>, <codeph>FLOAT</codeph>, <codeph>DOUBLE</codeph>, <codeph>BOOLEAN</codeph>,
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<codeph>STRING</codeph>, <codeph>TIMESTAMP</codeph>.
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</p>
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<p>
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For full details about Impala SQL syntax and semantics, see
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<xref href="impala_langref_sql.xml#langref_sql"/>.
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</p>
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<p>
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Most HiveQL <codeph>SELECT</codeph> and <codeph>INSERT</codeph> statements run unmodified with Impala. For
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information about Hive syntax not available in Impala, see
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<xref href="impala_langref_unsupported.xml#langref_hiveql_delta"/>.
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</p>
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<p>
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For a list of the built-in functions available in Impala queries, see
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<xref href="impala_functions.xml#builtins"/>.
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</p>
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<p outputclass="toc"/>
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</conbody>
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</concept>
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