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<th width="60%" align="center">Chapter 12.
The DbSequence Handle
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<h2 class="title" style="clear: both"><a id="seqstat"></a>DbSequence::stat()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
DbSequence::stat(DB_SEQUENCE_STAT **spp, u_int32_t flags); </pre>
<p>
The <code class="methodname">DbSequence::stat()</code> method creates a statistical structure and
copies a pointer to it into user-specified memory locations.
Specifically, if <span class="bold"><strong>spp</strong></span> is non-NULL, a
pointer to the statistics for the database are copied into the memory
location to which it refers.
</p>
<p>
Statistical structures are stored in allocated memory. If
application-specific allocation routines have been declared (see
<a class="xref" href="envset_alloc.html" title="DbEnv::set_alloc()">DbEnv::set_alloc()</a>
for more information), they are used to allocate the memory;
otherwise, the standard C library <span class="bold"><strong>malloc</strong></span>(3) is used. The caller is responsible
for deallocating the memory. To deallocate the memory, free the
memory reference; references inside the returned memory need not be
individually freed.
</p>
<p>
In the presence of multiple threads or processes accessing an active
sequence, the information returned by <code class="methodname">DbSequence::stat()</code> may be
out-of-date.
</p>
<p>
The <code class="methodname">DbSequence::stat()</code> method cannot be transaction-protected. For
this reason, it should be called in a thread of control that has no
open cursors or active transactions.
</p>
<p>
The <code class="methodname">DbSequence::stat()</code> <span>
<span>
method either returns a non-zero error value or throws an
exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</span>
</span>
</p>
<p>
The statistics are stored in a structure of type <code class="literal">DB_SEQUENCE_STAT</code>.
The following fields will be filled in:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<span class="bold"><strong>int32_t st_cache_size;</strong></span>
</p>
<p>
The number of values that will be cached in this handle.
</p>
</li>
<li>
<p>
<span class="bold"><strong>db_seq_t st_current;</strong></span>
</p>
<p>
The current value of the sequence in the database.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_flags;</strong></span>
</p>
<p>
The flags value for the sequence.
</p>
</li>
<li>
<p>
<span class="bold"><strong>db_seq_t st_last_value;</strong></span>
</p>
<p>
The last cached value of the sequence.
</p>
</li>
<li>
<p>
<span class="bold"><strong>db_seq_t st_min;</strong></span>
</p>
<p>
The minimum permitted value of the sequence.
</p>
</li>
<li>
<p>
<span class="bold"><strong>db_seq_t st_max;</strong></span>
</p>
<p>
The maximum permitted value of the sequence.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_nowait;</strong></span>
</p>
<p>
The number of times that a thread of control was able to obtain handle
mutex without waiting.
</p>
</li>
<li>
<p>
<span class="bold"><strong>db_seq_t st_value;</strong></span>
</p>
<p>
The current cached value of the sequence.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_wait;</strong></span>
</p>
<p>
The number of times a thread of control was forced to wait on the
handle mutex.
</p>
</li>
</ul>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp10208144"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp10169184"></a>flags</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>flags</strong></span> parameter must be set by
bitwise inclusively <span class="bold"><strong>OR</strong></span>'ing together
one or more of the following values:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">DB_STAT_ALL</code>
</p>
<p>
Display all available information.
</p>
</li>
<li>
<p>
<code class="literal">DB_STAT_CLEAR</code>
</p>
<p>
Reset statistics after printing their values.
</p>
</li>
</ul>
</div>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp10214904"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="seq.html" title="Chapter 12. The DbSequence Handle">DbSequence</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp10216320"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="seq.html#seqlist" title="Sequences and Related Methods">Sequences and Related Methods</a>
</p>
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