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<span id="runningHeaderText">EXPLAIN</span> </td>
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<span id="nsrTitle">SQLite Language Reference Documentation</span>
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<a id="exampleSectionLink" href="#codeExampleToggle" onclick="OpenSection(codeExampleToggle)">Example</a>
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<h1 class="heading">
SQL As Understood By SQLite</h1>
<h4>
EXPLAIN</h4>
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<i><font color="#ff3434">sql-statement</font></i> ::=</td>
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<b><font color="#2c2cf0">EXPLAIN </font></b><i><font color="#ff3434">sql-statement</font></i><b><font
color="#2c2cf0"></font></b></td>
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<p>
The EXPLAIN command modifier is a non-standard extension. The idea comes from a similar command found in PostgreSQL, but the operation is completely different.</p>
<p>
If the EXPLAIN keyword appears before any
other SQLite SQL command then instead
of actually executing the command, the SQLite library will report back the sequence
of virtual machine instructions it would have used to execute the command had the
EXPLAIN keyword not been present. For additional information about virtual machine
instructions see the <a href="http://www.sqlite.org/arch.html">architecture description</a>
or the documentation on <a href="http://www.sqlite.org/opcode.html">available opcodes</a>
for the virtual machine.</p>
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