docs/api_reference/CXX/dbset_q_extentsize.html

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  21           <th colspan="3" align="center">Db::set_q_extentsize()</th>
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  25           <th width="60%" align="center">Chapter 2.
  26                 The Db Handle
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  37             <h2 class="title" style="clear: both"><a id="dbset_q_extentsize"></a>Db::set_q_extentsize()</h2>
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  41       <pre class="programlisting">#include &lt;db_cxx.h&gt;
  42
  43 int
  44 Db::set_q_extentsize(u_int32_t extentsize); </pre>
  45       <p>
  46          Set the size of the extents used to hold pages in a Queue database,
  47          specified as a number of pages.  Each extent is created as a separate
  48          physical file.  If no extent size is set, the default behavior is to
  49          create only a single underlying database file.
  50     </p>
  51       <p>
  52          For information on tuning the extent size, see <a href="../../programmer_reference/rq_conf.html#am_conf_extentsize" class="olink">Selecting a extent size</a>.
  53     </p>
  54       <p>
  55          The <code class="methodname">Db::set_q_extentsize()</code> method configures a database, not only
  56          operations performed using the specified <a class="link" href="db.html" title="Chapter 2.  The Db Handle">Db</a>
  57          handle.
  58     </p>
  59       <p>
  60          The <code class="methodname">Db::set_q_extentsize()</code> method may not be called after the
  61          <a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a>  method is called. If
  62          the database already exists when
  63          <a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a>  is called, the
  64          information specified to <code class="methodname">Db::set_q_extentsize()</code> will be ignored.
  65     </p>
  66       <p>
  67          The <code class="methodname">Db::set_q_extentsize()</code> <span>
  68
  69             <span>
  70                 method either returns a non-zero error value or throws an
  71                 exception that encapsulates a non-zero error value on
  72                 failure, and returns 0 on success.
  73             </span>
  74         </span>
  75     </p>
  76       <div class="sect2" lang="en" xml:lang="en">
  77         <div class="titlepage">
  78           <div>
  79             <div>
  80               <h3 class="title"><a id="idp440232"></a>Parameters</h3>
  81             </div>
  82           </div>
  83         </div>
  84         <div class="sect3" lang="en" xml:lang="en">
  85           <div class="titlepage">
  86             <div>
  87               <div>
  88                 <h4 class="title"><a id="idp451352"></a>extentsize</h4>
  89               </div>
  90             </div>
  91           </div>
  92           <p>
  93                           The <span class="bold"><strong>extentsize</strong></span> parameter is the
  94                           number of pages in a Queue database extent.
  95                      </p>
  96         </div>
  97       </div>
  98       <div class="sect2" lang="en" xml:lang="en">
  99         <div class="titlepage">
 100           <div>
 101             <div>
 102               <h3 class="title"><a id="idp436720"></a>Errors</h3>
 103             </div>
 104           </div>
 105         </div>
 106         <p>
 107                          The <code class="methodname">Db::set_q_extentsize()</code> <span>
 108
 109             <span>
 110                 method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
 111                 exception, encapsulating one of the following non-zero errors, or return one
 112                 of the following non-zero errors:
 113             </span>
 114         </span>
 115                     </p>
 116         <div class="sect3" lang="en" xml:lang="en">
 117           <div class="titlepage">
 118             <div>
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 120                 <h4 class="title"><a id="idp456000"></a>EINVAL</h4>
 121               </div>
 122             </div>
 123           </div>
 124           <p>
 125                 If the method was called after <a class="xref" href="dbopen.html" title="Db::open()">Db::open()</a>
 126                 was called; or if an invalid flag value or parameter was specified.
 127             </p>
 128         </div>
 129       </div>
 130       <div class="sect2" lang="en" xml:lang="en">
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 134               <h3 class="title"><a id="idp435552"></a>Class</h3>
 135             </div>
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 138         <p>
 139                 <a class="link" href="db.html" title="Chapter 2.  The Db Handle">Db</a>
 140             </p>
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 149         </div>
 150         <p>
 151                      <a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a>
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