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            <h2 class="title" style="clear: both"><a id="reppriority"></a>DbEnv::rep_set_priority()</h2>
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      <pre class="programlisting">#include &lt;db_cxx.h&gt;
 
int
DbEnv::rep_set_priority(u_int32_t priority); </pre>
      <p>
         The <code class="methodname">DbEnv::rep_set_priority()</code> method specifies the database
         environment's priority in replication group elections.  A special
         value of 0 indicates that this environment cannot be a replication
         group master.
    </p>
      <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
        <h3 class="title">Note</h3>
        <p>
            The 
            <a class="xref" href="repmgrset_ack_policy.html" title="DbEnv::repmgr_set_ack_policy()">DbEnv::repmgr_set_ack_policy()</a> 
            method describes <span class="emphasis"><em>electable peers</em></span>, which
            are replication sites with a non-zero priority. For some
            acknowledgement policies, Replication Manager's computation of
            the durability result for each new update transaction is
            sensitive to whether each site in the group is a peer.
            Therefore, if you change a site's priority from a non-zero
            value to <code class="literal">0</code>, or from <code class="literal">0</code> to
            a non-zero value, this can invalidate the durability result of
            previously committed transactions.
        </p>
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      <p>
         The database environment's replication subsystem may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.  The syntax
         of the entry in that file is a single line with the string
         "rep_set_priority", one or more whitespace characters, and the
         priority of this site. For example, "rep_set_priority 1" sets the
         priority of this site to 1. Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read
         when the database environment is opened, it will silently overrule
         configuration done before that time.
    </p>
      <p>
        Note that if the application never explicitly sets a priority, then
        a default value of 100 is used. In preferred master mode, priority
        values for each site are automatically set and any attempt to change
        them results in an error.
    </p>
      <p>
         The <code class="methodname">DbEnv::rep_set_priority()</code> method configures a database
         environment, not only operations performed using the specified 
         <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  handle.
    </p>
      <p>
         The <code class="methodname">DbEnv::rep_set_priority()</code> method may be called at any time
         during the life of the application.
    </p>
      <p>
         The <code class="methodname">DbEnv::rep_set_priority()</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>
      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idp5410656"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp5410008"></a>priority</h4>
              </div>
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          <p>
                          The priority of this database environment in the replication group.  The
                          priority must be a non-zero integer, or 0 if this environment cannot be a
                          replication group master.  (See 
                          <a href="../../programmer_reference/rep_pri.html" class="olink">Replication environment priorities</a> 
                          for more information).
                     </p>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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              <h3 class="title"><a id="idp5373184"></a>Errors</h3>
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        <p>
             The <code class="methodname">DbEnv::rep_set_priority()</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">
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              <div>
                <h4 class="title"><a id="idp5420128"></a>EINVAL</h4>
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          <p>
                If changing the automatically set priority value in
                Replication Manager preferred master mode.
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idp5419048"></a>Class</h3>
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          </div>
        </div>
        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp5401536"></a>See Also</h3>
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          </div>
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        <p>
                     <a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a> 
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