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+<!-- keywords: sqlite3_stmt_explain -->
+<div class=nosearch>
+<a href="../c3ref/intro.html"><h2>SQLite C Interface</h2></a>
+<h2>Change The EXPLAIN Setting For A Prepared Statement</h2>
+</div>
+<blockquote><pre>
+int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode);
+</pre></blockquote>
+<p>
+The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN
+setting for <a href="../c3ref/stmt.html">prepared statement</a> S. If E is zero, then S becomes
+a normal prepared statement. If E is 1, then S behaves as if
+its SQL text began with "<a href="../lang_explain.html">EXPLAIN</a>". If E is 2, then S behaves as if
+its SQL text began with "<a href="../eqp.html">EXPLAIN QUERY PLAN</a>".</p>
+
+<p>Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared.
+SQLite tries to avoid a reprepare, but a reprepare might be necessary
+on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode.</p>
+
+<p>Because of the potential need to reprepare, a call to
+sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be
+reprepared because it was created using <a href="../c3ref/prepare.html">sqlite3_prepare()</a> instead of
+the newer <a href="../c3ref/prepare.html">sqlite3_prepare_v2()</a> or <a href="../c3ref/prepare.html">sqlite3_prepare_v3()</a> interfaces and
+hence has no saved SQL text with which to reprepare.</p>
+
+<p>Changing the explain setting for a prepared statement does not change
+the original SQL text for the statement. Hence, if the SQL text originally
+began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0)
+is called to convert the statement into an ordinary statement, the EXPLAIN
+or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S)
+output, even though the statement now acts like a normal SQL statement.</p>
+
+<p>This routine returns SQLITE_OK if the explain mode is successfully
+changed, or an error code if the explain mode could not be changed.
+The explain mode cannot be changed while a statement is active.
+Hence, it is good practice to call <a href="../c3ref/reset.html">sqlite3_reset(S)</a>
+immediately prior to calling sqlite3_stmt_explain(S,E).
+</p><p>See also lists of
+ <a href="../c3ref/objlist.html">Objects</a>,
+ <a href="../c3ref/constlist.html">Constants</a>, and
+ <a href="../c3ref/funclist.html">Functions</a>.</p>
+