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