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36      <p>
37        Both the <code class="classname">Environment</code> and
38        <code class="classname">Database</code> classes provide methods that are useful
39        for manipulating databases. These methods are:
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44            <p>
45              <code class="methodname">Database.getDatabaseName()</code>
46            </p>
47            <p>Returns the database's name.</p>
48            <a id="je_db3.1"></a>
49            <pre class="programlisting">String dbName = myDatabase.getDatabaseName();</pre>
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51          <li>
52            <p>
53              <code class="methodname">Database.rename()</code>
54            </p>
55            <p>
56                Renames the specified database. If no value is given for the 
57				<em class="parameter"><code>database</code></em> parameter, then the entire file
58				referenced by this method is renamed.
59            </p>
60            <p>
61				Never rename a database that has handles opened for it. Never rename a file that
62				contains databases with opened handles.
63			</p>
64            <a id="java_db9"></a>
65            <pre class="programlisting">import java.io.FileNotFoundException;
66...
67myDatabase.close();
68try {
69    myDatabase.rename("mydb.db",     // Database file to rename
70                      null,          // Database to rename. Not used so
71                                     // the entire file is renamed.
72                      "newdb.db",    // New name to use.
73                      null);         // DatabaseConfig object. 
74                                     // None provided.
75} catch (FileNotFoundException fnfe) {
76    // Exception handling goes here
77}</pre>
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80            <p>
81              <code class="methodname">Environment.truncateDatabase()</code>
82            </p>
83            <p>
84            Deletes every record in the database and optionally returns the
85            number of records that were deleted. Note that it is much less
86            expensive to truncate a database without counting the number of
87            records deleted than it is to truncate and count.
88        </p>
89            <a id="je_db5"></a>
90            <pre class="programlisting">int numDiscarded = 
91    myEnv.truncate(null,                          // txn handle
92                   myDatabase.getDatabaseName(),  // database name
93                   true);                         // If true, then the 
94                                                  // number of records 
95                                                  // deleted are counted.
96System.out.println("Discarded " + numDiscarded +
97                   " records from database " + 
98                   myDatabase.getDatabaseName()); </pre>
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