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906 lines
36 KiB
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<title>Db::stat()</title>
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<link rel="stylesheet" href="apiReference.css" type="text/css" />
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<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
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<link rel="start" href="index.html" title="Berkeley DB C++ API Reference" />
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<link rel="up" href="db.html" title="Chapter 2. The Db Handle" />
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<link rel="prev" href="dbset_re_source.html" title="Db::set_re_source()" />
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<link rel="next" href="dbstat_print.html" title="Db::stat_print()" />
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</head>
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<body>
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<div xmlns="" class="navheader">
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<div class="libver">
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<p>Library Version 11.2.5.2</p>
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</div>
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<table width="100%" summary="Navigation header">
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<tr>
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<th colspan="3" align="center">Db::stat()</th>
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</tr>
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<tr>
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<td width="20%" align="left"><a accesskey="p" href="dbset_re_source.html">Prev</a> </td>
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<th width="60%" align="center">Chapter 2.
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The Db Handle
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</th>
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<td width="20%" align="right"> <a accesskey="n" href="dbstat_print.html">Next</a></td>
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</tr>
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</table>
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<hr />
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</div>
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<div class="sect1" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h2 class="title" style="clear: both"><a id="dbstat"></a>Db::stat()</h2>
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</div>
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</div>
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</div>
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<pre class="programlisting">#include <db_cxx.h>
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int
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Db::stat(void *sp, u_int32_t flags); </pre>
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<p>
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The <code class="methodname">Db::stat()</code> method creates a statistical structure and copies a
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pointer to it into user-specified memory locations. Specifically, if
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<span class="bold"><strong>sp</strong></span> is non-NULL, a pointer to the
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statistics for the database are copied into the memory location to
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which it refers.
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</p>
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<p>
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The <code class="methodname">Db::stat()</code> <span>
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<span>
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method either returns a non-zero error value or throws an
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exception that encapsulates a non-zero error value on
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failure, and returns 0 on success.
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</span>
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</span>
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</p>
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<div class="sect2" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h3 class="title"><a id="id3600567"></a>Parameters</h3>
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</div>
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</div>
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</div>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3600564"></a>txnid</h4>
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</div>
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</div>
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</div>
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<p>
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If the operation is part of an application-specified transaction, the
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<span class="bold"><strong>txnid</strong></span> parameter is a transaction
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handle returned from <a class="xref" href="txnbegin.html" title="DbEnv::txn_begin()">DbEnv::txn_begin()</a>; if the
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operation is part of a Berkeley DB Concurrent Data Store group, the
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<span class="bold"><strong>txnid</strong></span> parameter is a handle returned
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from <a class="xref" href="envcdsgroup_begin.html" title="DbEnv::cdsgroup_begin()">DbEnv::cdsgroup_begin()</a>;
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otherwise NULL. If no transaction handle is specified, but the
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operation occurs in a transactional database, the operation will be
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implicitly transaction protected.
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</p>
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</div>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3600166"></a>flags</h4>
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</div>
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</div>
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</div>
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<p>
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The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
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or one of the following values:
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</p>
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<div class="itemizedlist">
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<ul type="disc">
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<li>
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<p><a id="stat_DB_FAST_STAT"></a>
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<code class="literal">DB_FAST_STAT</code>
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</p>
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<p>
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Return only the values which do not require traversal of the database.
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Among other things, this flag makes it possible for applications to
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request key and record counts without incurring the performance
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penalty of traversing the entire database.
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</p>
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</li>
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<li>
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<p><a id="stat_DB_READ_COMMITTED"></a>
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<code class="literal">DB_READ_COMMITTED</code>
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</p>
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<p>
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Database items read during a transactional call will have degree 2
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isolation. This ensures the stability of the data items read during
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the stat operation but permits that data to be modified or deleted by
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other transactions prior to the commit of the specified transaction.
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</p>
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</li>
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<li>
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<p><a id="stat_DB_READ_UNCOMMITTED"></a>
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<code class="literal">DB_READ_UNCOMMITTED</code>
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</p>
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<p>
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Database items read during a transactional call will have degree 1
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isolation, including modified but not yet committed data. Silently
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ignored if the
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<a class="link" href="dbopen.html#dbopen_DB_READ_UNCOMMITTED">DB_READ_UNCOMMITTED</a>
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flag was not specified when the underlying database was opened.
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</p>
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</li>
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</ul>
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</div>
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</div>
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</div>
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<div class="sect2" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h3 class="title"><a id="id3600633"></a>Statistical Structure</h3>
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</div>
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</div>
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</div>
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<p>
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Statistical structures are stored in allocated memory. If
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application-specific allocation routines have been declared (see
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<a class="xref" href="envset_alloc.html" title="DbEnv::set_alloc()">DbEnv::set_alloc()</a>
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for more information), they are used to allocate the
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memory; otherwise, the standard C library
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<span class="bold"><strong>malloc</strong></span>(3) is used. The caller is
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responsible for deallocating the memory. To deallocate the memory, free the
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memory reference; references inside the returned memory need not be
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individually freed.
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</p>
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<p>
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If the DB_FAST_STAT flag has not been specified, the
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<code class="methodname">Db::stat()</code> method will
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access some of or all the pages in the database, incurring a severe
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performance penalty as well as possibly flushing the underlying buffer pool.
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</p>
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<p>
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In the presence of multiple threads or processes accessing an active
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database, the information returned by DB->stat may be out-of-date.
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</p>
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<p>
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If the database was not opened read-only and the DB_FAST_STAT flag was not
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specified, the cached key and record numbers will be updated after the
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statistical information has been gathered.
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</p>
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<p>
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The <code class="methodname">Db::stat()</code> method may not be called before the
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<a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a>
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method is called.
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</p>
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<p>
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The <code class="methodname">Db::stat()</code> method returns
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a non-zero error value on failure and 0 on success.
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</p>
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<div class="sect3" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h4 class="title"><a id="id3600728"></a>Hash Statistics</h4>
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</div>
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</div>
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</div>
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<p>
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In the case of a Hash database, the statistics are stored in a
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structure of type <code class="literal">DB_HASH_STAT</code>. The following fields will be filled
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in:
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</p>
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<div class="itemizedlist">
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<ul type="disc">
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<li>
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<p>
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<code class="literal">uintmax_t hash_bfree;</code>
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</p>
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<p>
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The number of bytes free on bucket pages.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_bigpages;</code>
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</p>
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<p>
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The number of big key/data pages.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">uintmax_t hash_big_bfree;</code>
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</p>
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<p>
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The number of bytes free on big item pages.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_buckets;</code>
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</p>
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<p>
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The number of hash buckets. Returned if DB_FAST_STAT is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_dup;</code>
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</p>
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<p>
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The number of duplicate pages.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">uintmax_t hash_dup_free;</code>
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</p>
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<p>
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The number of bytes free on duplicate pages.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_ffactor;</code>
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</p>
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<p>
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The desired fill factor (number of items per bucket) specified at
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database-creation time. Returned if DB_FAST_STAT is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_free;</code>
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</p>
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<p>
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The number of pages on the free list.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_magic;</code>
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</p>
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<p>
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Magic number that identifies the file as a Hash file. Returned if
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DB_FAST_STAT is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_metaflags;</code>
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</p>
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<p>
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Reports internal flags. For internal use
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only.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_ndata;</code>
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</p>
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<p>
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The number of key/data pairs in the database. If DB_FAST_STAT was
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specified the count will be the last saved value unless it has never
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been calculated, in which case it will be 0. Returned if DB_FAST_STAT
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is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_nkeys;</code>
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</p>
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<p>
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The number of unique keys in the database. If DB_FAST_STAT was
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specified the count will be the last saved value unless it has never
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been calculated, in which case it will be 0. Returned if DB_FAST_STAT
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is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_overflows;</code>
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</p>
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<p>
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The number of overflow pages (overflow pages are pages that contain
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items that did not fit in the main bucket page).
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</p>
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</li>
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<li>
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<p>
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<code class="literal">uintmax_t hash_ovfl_free;</code>
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</p>
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<p>
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The number of bytes free on overflow pages.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_pagecnt;</code>
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</p>
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<p>
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The number of pages in the database. Returned if DB_FAST_STAT is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_pagesize;</code>
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</p>
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<p>
|
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The underlying database page (and bucket) size, in bytes. Returned if
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DB_FAST_STAT is set.
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</p>
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</li>
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<li>
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<p>
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<code class="literal">u_int32_t hash_version;</code>
|
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</p>
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<p>
|
|||
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The version of the Hash database. Returned if DB_FAST_STAT is set.
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</p>
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</li>
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|
|
</ul>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect3" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h4 class="title"><a id="id3600902"></a>Heap Statistics</h4>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
In the case of a Heap database, the statistics are stored in a
|
|||
|
|
structure of type <code class="literal">DB_HEAP_STAT</code>. The following fields will be filled
|
|||
|
|
in:
|
|||
|
|
</p>
|
|||
|
|
<div class="itemizedlist">
|
|||
|
|
<ul type="disc">
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_magic;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Magic number that identifies the file as a Heap file. Returned if
|
|||
|
|
DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_version;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The version of the Heap database. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_metaflags;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Reports internal flags. For internal use
|
|||
|
|
only.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_nrecs;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Reports the number of records in the Heap
|
|||
|
|
database. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_pagecnt;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The number of pages in the database. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_pagesize;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The underlying database page (and bucket) size, in bytes. Returned if
|
|||
|
|
DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t heap_nregions;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The number of regions in the Heap database. Returned if
|
|||
|
|
DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
</ul>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect3" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h4 class="title"><a id="id3600931"></a>Btree and Recno Statistics</h4>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
In the case of a Btree or Recno database, the
|
|||
|
|
statistics are stored in a structure of type
|
|||
|
|
<code class="literal">DB_BTREE_STAT</code>. The following fields
|
|||
|
|
will be filled in:
|
|||
|
|
</p>
|
|||
|
|
<div class="itemizedlist">
|
|||
|
|
<ul type="disc">
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_dup_pg;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of database duplicate pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">uintmax_t bt_dup_pgfree;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of bytes free in database duplicate pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_empty_pg;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of empty database pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_free;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of pages on the free list.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_int_pg;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of database internal pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">uintmax_t bt_int_pgfree;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of bytes free in database internal pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_leaf_pg;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of database leaf pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">uintmax_t bt_leaf_pgfree;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of bytes free in database leaf pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_levels;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of levels in the database.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_magic;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Magic number that identifies the file as a Btree database. Returned
|
|||
|
|
if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_metaflags;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Reports internal flags. For internal use
|
|||
|
|
only.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_minkey;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The minimum keys per page. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_ndata;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
For the Btree Access Method, the number of key/data pairs in the
|
|||
|
|
database. If the DB_FAST_STAT flag is not specified, the count will
|
|||
|
|
be exact. Otherwise, the count will be the last saved value unless it
|
|||
|
|
has never been calculated, in which case it will be 0.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
For the Recno Access Method, the number of records in the database.
|
|||
|
|
If the database was configured with mutable record numbers (see
|
|||
|
|
<a class="link" href="dbset_flags.html#dbset_flags_DB_RENUMBER">DB_RENUMBER</a>),
|
|||
|
|
the count will be exact. Otherwise, if the DB_FAST_STAT flag is specified
|
|||
|
|
the count will be exact but will include deleted and implicitly
|
|||
|
|
created records; if the DB_FAST_STAT flag is not specified, the count
|
|||
|
|
will be exact and will not include deleted or implicitly created
|
|||
|
|
records.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_nkeys;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
For the Btree Access Method, the number of keys in the database. If
|
|||
|
|
the DB_FAST_STAT flag is not specified or the database was configured
|
|||
|
|
to support record numbers (see
|
|||
|
|
<a class="link" href="dbset_flags.html#dbset_flags_DB_RECNUM">DB_RECNUM</a>),
|
|||
|
|
the count will be exact. Otherwise, the count will be the last saved
|
|||
|
|
value unless it has never been calculated, in which case it will be 0.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
For the Recno Access Method, the number of records in the database.
|
|||
|
|
If the database was configured with mutable record numbers (see
|
|||
|
|
<a class="link" href="dbset_flags.html#dbset_flags_DB_RENUMBER">DB_RENUMBER</a>),
|
|||
|
|
the count will be exact. Otherwise, if the DB_FAST_STAT flag is specified
|
|||
|
|
the count will be exact but will include deleted and implicitly
|
|||
|
|
created records; if the DB_FAST_STAT flag is not specified, the count
|
|||
|
|
will be exact and will not include deleted or implicitly created
|
|||
|
|
records.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_over_pg;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of database overflow pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">uintmax_t bt_over_pgfree;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of bytes free in database overflow pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_pagecnt;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The number of pages in the database. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_pagesize;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The underlying database page size, in bytes. Returned if DB_FAST_STAT
|
|||
|
|
is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_re_len;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The length of fixed-length records. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_re_pad;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The padding byte value for fixed-length records. Returned if
|
|||
|
|
DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t bt_version;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The version of the Btree database. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
</ul>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect3" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h4 class="title"><a id="id3600391"></a>Queue Statistics</h4>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
In the case of a Queue database, the statistics are
|
|||
|
|
stored in a structure of type
|
|||
|
|
<code class="literal">DB_QUEUE_STAT</code>. The following fields
|
|||
|
|
will be filled in:
|
|||
|
|
</p>
|
|||
|
|
<div class="itemizedlist">
|
|||
|
|
<ul type="disc">
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_cur_recno;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Next available record number. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_extentsize;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Underlying database extent size, in pages. Returned if DB_FAST_STAT
|
|||
|
|
is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_first_recno;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
First undeleted record in the database. Returned if DB_FAST_STAT is
|
|||
|
|
set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_magic;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Magic number that identifies the file as a Queue file. Returned if
|
|||
|
|
DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_metaflags;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Reports internal flags. For internal use
|
|||
|
|
only.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_nkeys;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The number of records in the database. If DB_FAST_STAT was specified
|
|||
|
|
the count will be the last saved value unless it has never been
|
|||
|
|
calculated, in which case it will be 0. Returned if DB_FAST_STAT is
|
|||
|
|
set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_ndata;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The number of records in the database. If DB_FAST_STAT was specified
|
|||
|
|
the count will be the last saved value unless it has never been
|
|||
|
|
calculated, in which case it will be 0. Returned if DB_FAST_STAT is
|
|||
|
|
set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_pages;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of pages in the database.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_pagesize;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Underlying database page size, in bytes. Returned if DB_FAST_STAT is
|
|||
|
|
set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_pgfree;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
Number of bytes free in database pages.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_re_len;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The length of the records. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_re_pad;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The padding byte value for the records. Returned if DB_FAST_STAT is
|
|||
|
|
set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
<li>
|
|||
|
|
<p>
|
|||
|
|
<code class="literal">u_int32_t qs_version;</code>
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The version of the Queue file type. Returned if DB_FAST_STAT is set.
|
|||
|
|
</p>
|
|||
|
|
</li>
|
|||
|
|
</ul>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect2" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h3 class="title"><a id="id3601270"></a>Errors</h3>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
The <code class="methodname">Db::stat()</code> <span>
|
|||
|
|
|
|||
|
|
<span>
|
|||
|
|
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
|
|||
|
|
exception, encapsulating one of the following non-zero errors, or return one
|
|||
|
|
of the following non-zero errors:
|
|||
|
|
</span>
|
|||
|
|
</span>
|
|||
|
|
</p>
|
|||
|
|
<div class="sect3" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h4 class="title"><a id="id3601667"></a> <span>DbRepHandleDeadException or</span> DB_REP_HANDLE_DEAD</h4>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
When a client synchronizes with the master, it is possible for committed
|
|||
|
|
transactions to be rolled back. This invalidates all the database and cursor
|
|||
|
|
handles opened in the replication environment. Once this occurs, an attempt to use
|
|||
|
|
such a handle will
|
|||
|
|
<span>
|
|||
|
|
throw a <a class="xref" href="dbrephandledead.html" title="DbRepHandleDeadException">DbRepHandleDeadException</a> (if
|
|||
|
|
your application is configured to throw exceptions), or
|
|||
|
|
</span>
|
|||
|
|
return <code class="literal">DB_REP_HANDLE_DEAD</code>.
|
|||
|
|
The application will need to discard the handle and open a new one in order to
|
|||
|
|
continue processing.
|
|||
|
|
</p>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect3" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h4 class="title"><a id="id3600719"></a><span>DbDeadlockException or </span>DB_REP_LOCKOUT</h4>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
The operation was blocked by client/master synchronization.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
<a class="xref" href="dbdeadlock.html" title="DbDeadlockException">DbDeadlockException</a> is thrown if
|
|||
|
|
your Berkeley DB API is configured to throw exceptions.
|
|||
|
|
Otherwise, <code class="literal">DB_REP_LOCKOUT</code> is returned.
|
|||
|
|
</p>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect3" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h4 class="title"><a id="id3600651"></a>EINVAL</h4>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
An invalid flag value or parameter was specified.
|
|||
|
|
</p>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect2" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h3 class="title"><a id="id3601714"></a>Class</h3>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
<a class="link" href="db.html" title="Chapter 2. The Db Handle">Db</a>
|
|||
|
|
</p>
|
|||
|
|
</div>
|
|||
|
|
<div class="sect2" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h3 class="title"><a id="id3600800"></a>See Also</h3>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
<a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a>
|
|||
|
|
</p>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="navfooter">
|
|||
|
|
<hr />
|
|||
|
|
<table width="100%" summary="Navigation footer">
|
|||
|
|
<tr>
|
|||
|
|
<td width="40%" align="left"><a accesskey="p" href="dbset_re_source.html">Prev</a> </td>
|
|||
|
|
<td width="20%" align="center">
|
|||
|
|
<a accesskey="u" href="db.html">Up</a>
|
|||
|
|
</td>
|
|||
|
|
<td width="40%" align="right"> <a accesskey="n" href="dbstat_print.html">Next</a></td>
|
|||
|
|
</tr>
|
|||
|
|
<tr>
|
|||
|
|
<td width="40%" align="left" valign="top">Db::set_re_source() </td>
|
|||
|
|
<td width="20%" align="center">
|
|||
|
|
<a accesskey="h" href="index.html">Home</a>
|
|||
|
|
</td>
|
|||
|
|
<td width="40%" align="right" valign="top"> Db::stat_print()</td>
|
|||
|
|
</tr>
|
|||
|
|
</table>
|
|||
|
|
</div>
|
|||
|
|
</body>
|
|||
|
|
</html>
|