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32            <h2 class="title" style="clear: both"><a id="ReplacingEntryWCursor"></a>Replacing Records Using Cursors</h2>
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36      <p>
37        You replace the data for a database record by using
38        
39
40        <span>
41            <code class="methodname">Cursor.putCurrent()</code>. 
42        </span>
43
44        
45            
46    </p>
47      <a id="java_cursor9"></a>
48      <pre class="programlisting">import com.sleepycat.db.Cursor;
49import com.sleepycat.db.Database;
50import com.sleepycat.db.DatabaseEntry;
51import com.sleepycat.db.LockMode;
52import com.sleepycat.db.OperationStatus; 
53
54...
55Cursor cursor = null;
56Database myDatabase = null;
57try {
58    ...
59    // Database open omitted for brevity
60    ...
61    // Create DatabaseEntry objects
62    // searchKey is some String.
63    DatabaseEntry theKey = new DatabaseEntry(searchKey.getBytes("UTF-8"));
64    DatabaseEntry theData = new DatabaseEntry();
65
66    // Open a cursor using a database handle
67    cursor = myDatabase.openCursor(null, null);
68
69    // Position the cursor. Ignoring the return value for clarity
70    OperationStatus retVal = cursor.getSearchKey(theKey, theData, 
71                                                 LockMode.DEFAULT);
72    
73    // Replacement data
74    String replaceStr = "My replacement string";
75    DatabaseEntry replacementData = 
76        new DatabaseEntry(replaceStr.getBytes("UTF-8"));
77    cursor.putCurrent(replacementData);
78} catch (Exception e) {
79    // Exception handling goes here
80} finally {
81   // Make sure to close the cursor
82   cursor.close();
83}</pre>
84      <p>
85        Note that you cannot change a record's key using this method; the key
86        parameter is always ignored when you replace a record.
87    </p>
88      <p>
89        When replacing the data portion of a record, if you are replacing a
90        record that is a member of a sorted duplicates set, then the replacement
91        will be successful only if the new record sorts identically to the old
92        record. This means that if you are replacing a record that is a member
93        of a sorted duplicates set, and if you are using the default
94        lexicographic sort, then the replacement will fail due to violating the
95        sort order. However, if you
96        provide a custom sort routine that, for example, sorts based on just a
97        few bytes out of the data item, then potentially you can perform
98        a direct replacement and still not violate the restrictions described
99        here.
100    </p>
101      <p>
102            <span>Under these circumstances, if</span>
103            
104        you want to replace the data contained by a duplicate record, 
105            <span>
106                and you are not using a custom sort routine, then
107            </span>
108        delete the record and create a new record with the desired key and data.
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