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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 <db_cxx.h>
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.
</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>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp9644720"></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="idp9644072"></a>priority</h4>
</div>
</div>
</div>
<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).
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<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>
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<h3 class="title"><a id="idp9626352"></a>See Also</h3>
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<a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a>
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