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Each constant designates a +different metric for sqlite3_stmt_scanstatus() to return.</p> + +<p>When the value returned to V is a string, space to hold that string is +managed by the prepared statement S and will be automatically freed when +S is finalized.</p> + +<p><dl> +<a name="sqlitescanstatnloop"></a> + <dt>SQLITE_SCANSTAT_NLOOP</dt> +<dd>The <a href="../c3ref/int64.html">sqlite3_int64</a> variable pointed to by the V parameter will be +set to the total number of times that the X-th loop has run.</dd></p> + +<p><a name="sqlitescanstatnvisit"></a> + <dt>SQLITE_SCANSTAT_NVISIT</dt> +<dd>The <a href="../c3ref/int64.html">sqlite3_int64</a> variable pointed to by the V parameter will be set +to the total number of rows examined by all iterations of the X-th loop.</dd></p> + +<p><a name="sqlitescanstatest"></a> + <dt>SQLITE_SCANSTAT_EST</dt> +<dd>The "double" variable pointed to by the V parameter will be set to the +query planner's estimate for the average number of rows output from each +iteration of the X-th loop. If the query planner's estimates was accurate, +then this value will approximate the quotient NVISIT/NLOOP and the +product of this value for all prior loops with the same SELECTID will +be the NLOOP value for the current loop.</p> + +<p><a name="sqlitescanstatname"></a> + <dt>SQLITE_SCANSTAT_NAME</dt> +<dd>The "const char *" variable pointed to by the V parameter will be set +to a zero-terminated UTF-8 string containing the name of the index or table +used for the X-th loop.</p> + +<p><a name="sqlitescanstatexplain"></a> + <dt>SQLITE_SCANSTAT_EXPLAIN</dt> +<dd>The "const char *" variable pointed to by the V parameter will be set +to a zero-terminated UTF-8 string containing the <a href="../eqp.html">EXPLAIN QUERY PLAN</a> +description for the X-th loop.</p> + +<p><a name="sqlitescanstatselectid"></a> + <dt>SQLITE_SCANSTAT_SELECT</dt> +<dd>The "int" variable pointed to by the V parameter will be set to the +"select-id" for the X-th loop. The select-id identifies which query or +subquery the loop is part of. The main query has a select-id of zero. +The select-id is the same value as is output in the first column +of an <a href="../eqp.html">EXPLAIN QUERY PLAN</a> query. +</dl> +</p><p>See also lists of + <a href="objlist.html">Objects</a>, + <a href="constlist.html">Constants</a>, and + <a href="funclist.html">Functions</a>.</p> + |