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   <h1 class="title topictitle1" id="ariaid-title1">SET Statement</h1>


   <div class="body conbody">

     <p class="p">
       The <code class="ph codeph">SET</code> statement specifies values for query options that control the
       runtime behavior of other statements within the same session.
     </p>


     <p class="p">
       When issued in <code class="ph codeph">impala-shell</code>, the <code class="ph codeph">SET</code> command is
       interpreted as an <code class="ph codeph">impala-shell</code> command that has differences from the SQL
       <code class="ph codeph">SET</code> statement. See
       <a class="xref" href="impala_shell_commands.html#shell_commands">impala-shell Command Reference</a> for the information about
       the <code class="ph codeph">SET</code> command in <code class="ph codeph">impala-shell</code>.
     </p>


     <p class="p">
         <strong class="ph b">Syntax:</strong>
       </p>


 <pre class="pre codeblock"><code>SET
 <span class="ph">SET ALL</span>
 SET <var class="keyword varname">query_option</var>=<var class="keyword varname">option_value</var>
 SET <var class="keyword varname">query_option</var>=""
 </code></pre>

     <p class="p">
       <code class="ph codeph">SET</code> and <code class="ph codeph">SET ALL</code> with no arguments return a result set
       consisting of all the applicable query options and their current values.
     </p>


     <p class="p">
       The <var class="keyword varname">query_option</var> and <var class="keyword varname">option_value</var> are
       case-insensitive.
     </p>


     <p class="p">
       Unlike the <code class="ph codeph">impala-shell</code> command version of <code class="ph codeph">SET</code>, when
       used as a SQL statement, the string values for <var class="keyword varname">option_value</var> need to be
       quoted, e.g. <code class="ph codeph">SET option="new_value"</code>.
     </p>


     <p class="p">
       The <code class="ph codeph">SET <var class="keyword varname">query_option</var> = ""</code> statement unsets the value
       of the <var class="keyword varname">query_option</var> in the current session, reverting it to the default
       state. In <code class="ph codeph">impala-shell</code>, use the <code class="ph codeph">UNSET</code> command to set a
       query option to it default.
     </p>


     <p class="p">
       Each query option has a specific allowed notation for its arguments. See
       <a class="xref" href="impala_query_options.html#query_options">Query Options for the SET Statement</a> for the details of each query
       option.
     </p>


     <p class="p">
         <strong class="ph b">Usage notes:</strong>
       </p>


     <p class="p">
       In <span class="keyword">Impala 2.11</span> and higher, the outputs of the <code class="ph codeph">SET</code>
       and <code class="ph codeph">SET ALL</code> statements were reorganized as below:
     </p>


     <ul class="ul">
       <li class="li">
         <p class="p">
           The options are divided into groups: <code class="ph codeph">Regular Query Options</code>,
           <code class="ph codeph">Advanced Query Options</code>, <code class="ph codeph">Development Query Options</code>,
           and <code class="ph codeph">Deprecated Query Options</code>.
         </p>

         <ul class="ul">
           <li class="li">
             <p class="p">
               The advanced options are intended for use in specific kinds of performance tuning
               and debugging scenarios.
             </p>

           </li>


           <li class="li">
             <p class="p">
               The development options are related to internal development of Impala or features
               that are not yet finalized. These options might be changed or removed without
               notice.
             </p>

           </li>


           <li class="li">
             <p class="p">
               The deprecated options are related to features that are removed or changed so that
               the options no longer have any purpose. These options might be removed in future
               versions.
             </p>

           </li>

         </ul>

       </li>


       <li class="li">
         <p class="p">
           By default, only the first two groups, regular and advanced, are displayed by the
           <code class="ph codeph">SET</code> command. Use <code class="ph codeph">SET ALL</code> to see all groups of
           options.
         </p>

       </li>


       <li class="li">
         <p class="p">
           <span class="keyword cmdname">impala-shell</span> options and user-specified variables are always
           displayed at the end of the list of query options, after all appropriate option
           groups.
         </p>

       </li>

     </ul>


     <p class="p">
         <strong class="ph b">Added in:</strong> <span class="keyword">Impala 2.0.0</span>
       </p>


     <p class="p">
       <code class="ph codeph">SET</code> has always been available as an <span class="keyword cmdname">impala-shell</span>
       command. Promoting it to a SQL statement lets you use this feature in client applications
       through the JDBC and ODBC APIs.
     </p>


     <p class="p">
         <strong class="ph b">HDFS permissions:</strong> This statement does not touch any HDFS files or directories,
         therefore no HDFS permissions are required.
       </p>


     <p class="p">
         <strong class="ph b">Related information:</strong>
       </p>


     <p class="p">
       See <a class="xref" href="impala_query_options.html#query_options">Query Options for the SET Statement</a> for the query options you can
       adjust using this statement.
     </p>


   </div>


 <div class="related-links">
 <ul class="ullinks">
 <li class="link ulchildlink"><strong><a href="../topics/impala_query_options.html">Query Options for the SET Statement</a></strong><br />
 </li>
 </ul>

 <div class="familylinks">
 <div class="parentlink"><strong>Parent topic:</strong> <a class="link" href="../topics/impala_langref_sql.html">Impala SQL Statements</a></div>
 </div>
 </div></body>
 </html>
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	<meta name="DC.rights.owner" content="(C) Copyright 2023" />
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	<meta name="DC.Title" content="SET Statement" />
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	<link rel="stylesheet" type="text/css" href="../commonltr.css" />
	<title>SET Statement</title>
	</head>
	<body id="set">


	<h1 class="title topictitle1" id="ariaid-title1">SET Statement</h1>






	<div class="body conbody">

	<p class="p">
	The <code class="ph codeph">SET</code> statement specifies values for query options that control the
	runtime behavior of other statements within the same session.
	</p>


	<p class="p">
	When issued in <code class="ph codeph">impala-shell</code>, the <code class="ph codeph">SET</code> command is
	interpreted as an <code class="ph codeph">impala-shell</code> command that has differences from the SQL
	<code class="ph codeph">SET</code> statement. See
	<a class="xref" href="impala_shell_commands.html#shell_commands">impala-shell Command Reference</a> for the information about
	the <code class="ph codeph">SET</code> command in <code class="ph codeph">impala-shell</code>.
	</p>


	<p class="p">
	<strong class="ph b">Syntax:</strong>
	</p>


	<pre class="pre codeblock"><code>SET
	<span class="ph">SET ALL</span>
	SET <var class="keyword varname">query_option</var>=<var class="keyword varname">option_value</var>
	SET <var class="keyword varname">query_option</var>=""
	</code></pre>

	<p class="p">
	<code class="ph codeph">SET</code> and <code class="ph codeph">SET ALL</code> with no arguments return a result set
	consisting of all the applicable query options and their current values.
	</p>


	<p class="p">
	The <var class="keyword varname">query_option</var> and <var class="keyword varname">option_value</var> are
	case-insensitive.
	</p>


	<p class="p">
	Unlike the <code class="ph codeph">impala-shell</code> command version of <code class="ph codeph">SET</code>, when
	used as a SQL statement, the string values for <var class="keyword varname">option_value</var> need to be
	quoted, e.g. <code class="ph codeph">SET option="new_value"</code>.
	</p>


	<p class="p">
	The <code class="ph codeph">SET <var class="keyword varname">query_option</var> = ""</code> statement unsets the value
	of the <var class="keyword varname">query_option</var> in the current session, reverting it to the default
	state. In <code class="ph codeph">impala-shell</code>, use the <code class="ph codeph">UNSET</code> command to set a
	query option to it default.
	</p>


	<p class="p">
	Each query option has a specific allowed notation for its arguments. See
	<a class="xref" href="impala_query_options.html#query_options">Query Options for the SET Statement</a> for the details of each query
	option.
	</p>


	<p class="p">
	<strong class="ph b">Usage notes:</strong>
	</p>


	<p class="p">
	In <span class="keyword">Impala 2.11</span> and higher, the outputs of the <code class="ph codeph">SET</code>
	and <code class="ph codeph">SET ALL</code> statements were reorganized as below:
	</p>


	<ul class="ul">
	<li class="li">
	<p class="p">
	The options are divided into groups: <code class="ph codeph">Regular Query Options</code>,
	<code class="ph codeph">Advanced Query Options</code>, <code class="ph codeph">Development Query Options</code>,
	and <code class="ph codeph">Deprecated Query Options</code>.
	</p>

	<ul class="ul">
	<li class="li">
	<p class="p">
	The advanced options are intended for use in specific kinds of performance tuning
	and debugging scenarios.
	</p>

	</li>


	<li class="li">
	<p class="p">
	The development options are related to internal development of Impala or features
	that are not yet finalized. These options might be changed or removed without
	notice.
	</p>

	</li>


	<li class="li">
	<p class="p">
	The deprecated options are related to features that are removed or changed so that
	the options no longer have any purpose. These options might be removed in future
	versions.
	</p>

	</li>

	</ul>

	</li>


	<li class="li">
	<p class="p">
	By default, only the first two groups, regular and advanced, are displayed by the
	<code class="ph codeph">SET</code> command. Use <code class="ph codeph">SET ALL</code> to see all groups of
	options.
	</p>

	</li>


	<li class="li">
	<p class="p">
	<span class="keyword cmdname">impala-shell</span> options and user-specified variables are always
	displayed at the end of the list of query options, after all appropriate option
	groups.
	</p>

	</li>

	</ul>


	<p class="p">
	<strong class="ph b">Added in:</strong> <span class="keyword">Impala 2.0.0</span>
	</p>


	<p class="p">
	<code class="ph codeph">SET</code> has always been available as an <span class="keyword cmdname">impala-shell</span>
	command. Promoting it to a SQL statement lets you use this feature in client applications
	through the JDBC and ODBC APIs.
	</p>


	<p class="p">
	<strong class="ph b">HDFS permissions:</strong> This statement does not touch any HDFS files or directories,
	therefore no HDFS permissions are required.
	</p>


	<p class="p">
	<strong class="ph b">Related information:</strong>
	</p>


	<p class="p">
	See <a class="xref" href="impala_query_options.html#query_options">Query Options for the SET Statement</a> for the query options you can
	adjust using this statement.
	</p>


	</div>


	<div class="related-links">
	<ul class="ullinks">
	<li class="link ulchildlink"><strong><a href="../topics/impala_query_options.html">Query Options for the SET Statement</a></strong><br />
	</li>
	</ul>

	<div class="familylinks">
	<div class="parentlink"><strong>Parent topic:</strong> <a class="link" href="../topics/impala_langref_sql.html">Impala SQL Statements</a></div>
	</div>
	</div></body>
	</html>