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<p>
Both the <code class="classname">Environment</code> and
<code class="classname">Database</code> classes provide methods that are useful
for manipulating databases. These methods are:
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<p>
<code class="methodname">Database.getDatabaseName()</code>
</p>
<p>Returns the database's name.</p>
<a id="je_db3.1"></a>
<pre class="programlisting">String dbName = myDatabase.getDatabaseName();</pre>
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<p>
<code class="methodname">Database.rename()</code>
</p>
<p>
Renames the specified database. If no value is given for the
<em class="parameter"><code>database</code></em> parameter, then the entire file
referenced by this method is renamed.
</p>
<p>
Never rename a database that has handles opened for it. Never rename a file that
contains databases with opened handles.
</p>
<a id="java_db9"></a>
<pre class="programlisting">import java.io.FileNotFoundException;
...
myDatabase.close();
try {
myDatabase.rename("mydb.db", // Database file to rename
null, // Database to rename. Not used so
// the entire file is renamed.
"newdb.db", // New name to use.
null); // DatabaseConfig object.
// None provided.
} catch (FileNotFoundException fnfe) {
// Exception handling goes here
}</pre>
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<p>
<code class="methodname">Environment.truncateDatabase()</code>
</p>
<p>
Deletes every record in the database and optionally returns the
number of records that were deleted. Note that it is much less
expensive to truncate a database without counting the number of
records deleted than it is to truncate and count.
</p>
<a id="je_db5"></a>
<pre class="programlisting">int numDiscarded =
myEnv.truncate(null, // txn handle
myDatabase.getDatabaseName(), // database name
true); // If true, then the
// number of records
// deleted are counted.
System.out.println("Discarded " + numDiscarded +
" records from database " +
myDatabase.getDatabaseName()); </pre>
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