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<p>
Both the <tt class="classname">Environment</tt> and
<tt class="classname">Database</tt> classes provide methods that are useful
for manipulating databases. These methods are:
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<tt class="methodname">Database.getDatabaseName()</tt>
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<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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<tt class="methodname">Database.rename()</tt>
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<p>
Renames the specified database. If no value is given for the
<i class="parameter"><tt>database</tt></i> 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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<tt class="methodname">Environment.truncateDatabase()</tt>
</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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