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- <h2 align="center">SQL As Understood By SQLite</h2></a><h1>EXPLAIN</h1><h4><a href="syntaxdiagrams.html#sql-stmt">sql-stmt:</a></h4><blockquote> <img alt="syntax diagram sql-stmt" src="images/syntax/sql-stmt.gif"></img> </blockquote>
- <p>An SQL statement can be preceded by the keyword "EXPLAIN" or
- by the phrase "EXPLAIN QUERY PLAN". Either modification causes the
- SQL statement to behave as a query and to return information about
- how the SQL statement would have operated if the EXPLAIN keyword or
- phrase had been omitted.</p>
- <p>When the EXPLAIN keyword appears by itself it causes the statement
- to behave as a query that returns the sequence of
- virtual machine instructions it would have
- used to execute the command had the EXPLAIN keyword not been present.
- When the EXPLAIN QUERY PLAN phrase appears, the statement returns
- high-level information about what indices would have been used.</p>
- <p>The output from EXPLAIN and EXPLAIN QUERY PLAN is intended for
- interactive analysis and troubleshooting only. The details of the
- output format are subject to change from one release of SQLite to the next.
- Applications should not use EXPLAIN or EXPLAIN QUERY PLAN since
- their behavior is undocumented, unspecified, and variable.</p>
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