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<!--$Id: seq_stat.so,v 1.8 2004/09/07 15:37:41 bostic Exp $-->
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<title>Berkeley DB: DB_SEQUENCE->stat</title>
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<h3>DB_SEQUENCE->stat</h3>
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<tt>
<h3><pre>
#include <db.h>
<p>
int
DB_SEQUENCE->stat(DB_SEQUENCE *db, void *sp, u_int32_t flags);
<p>
int
DB_SEQUENCE->stat_print(DB_SEQUENCE *db, u_int32_t flags);
</pre></h3>
<hr size=1 noshade>
<h3>Description: DB_SEQUENCE->stat</h3>
<p>The DB_SEQUENCE->stat method creates a statistical structure and copies a
pointer to it into user-specified memory locations. Specifically, if
<b>sp</b> 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 href="../api_c/env_set_alloc.html">DB_ENV->set_alloc</a> for more
information), they are used to allocate the memory; otherwise, the
standard C library <b>malloc</b>(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 DB_SEQUENCE->stat may be out-of-date.</p>
<p>The DB_SEQUENCE->stat 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 statistics are stored in a structure of type DB_SEQUENCE_STAT. The
following fields will be filled in:</p>
<dl compact>
<dt>u_int32_t st_wait;<dd>The number of times a thread of control was forced to wait on the
handle mutex.
<dt>u_int32_t st_nowait;<dd>The number of times that a thread of control was able to obtain handle
mutex without waiting.
<dt>db_seq_t st_current;<dd>The current value of the sequence in the database.
<dt>db_seq_t st_value;<dd>The current cached value of the sequence.
<dt>db_seq_t st_last_value;<dd>The last cached value of the sequence.
<dt>db_seq_t st_min;<dd>The minimum permitted value of the sequence.
<dt>db_seq_t st_max;<dd>The maximum permitted value of the sequence.
<dt>int32_t st_cache_size;<dd>The number of values that will be cached in this handle.
<dt>u_int32_t st_flags;<dd>The flags value for the sequence.
</dl>
<h3>Parameters</h3>
<dl compact>
<dt><b>flags</b><dd>The <b>flags</b> parameter must be set by bitwise inclusively <b>OR</b>'ing together one or more
of the following values:
<dl compact>
<dt><a name="DB_STAT_CLEAR">DB_STAT_CLEAR</a><dd>Reset statistics after printing their values.
</dl>
</dl>
<p>The DB_SEQUENCE->stat_print method
returns a non-zero error value on failure
and 0 on success.
</p>
<hr size=1 noshade>
<h3>Description: DB_SEQUENCE->stat_print</h3>
<p>The DB_SEQUENCE->stat_print method prints diagnostic information to the output
channel described by the <a href="../api_c/env_set_msgfile.html">DB_ENV->set_msgfile</a> method.</p>
<h3>Parameters</h3>
<dl compact>
<dt><b>flags</b><dd>The <b>flags</b> parameter must be set by bitwise inclusively <b>OR</b>'ing together one or more
of the following values:
<dl compact>
<dt><a name="DB_STAT_CLEAR">DB_STAT_CLEAR</a><dd>Reset statistics after printing their values.
</dl>
</dl>
<hr size=1 noshade>
<h3>Class</h3>
<a href="../api_c/seq_class.html">DB_SEQUENCE</a>
<h3>See Also</h3>
<a href="../api_c/seq_list.html">Sequences and Related Methods</a>
</tt>
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