Replacing Records Using Cursors
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## Replacing Records Using Cursors

You replace the data for a database record by using `Cursor.putCurrent()`.

    import com.sleepycat.db.Cursor;
    import com.sleepycat.db.Database;
    import com.sleepycat.db.DatabaseEntry;
    import com.sleepycat.db.LockMode;
    import com.sleepycat.db.OperationStatus;

    ...
    Cursor cursor = null;
    Database myDatabase = null;
    try {
        ...
        // Database open omitted for brevity
        ...
        // Create DatabaseEntry objects
        // searchKey is some String.
        DatabaseEntry theKey = new DatabaseEntry(searchKey.getBytes("UTF-8"));
        DatabaseEntry theData = new DatabaseEntry();

        // Open a cursor using a database handle
        cursor = myDatabase.openCursor(null, null);

        // Position the cursor. Ignoring the return value for clarity
        OperationStatus retVal = cursor.getSearchKey(theKey, theData,
                                                     LockMode.DEFAULT);

        // Replacement data
        String replaceStr = "My replacement string";
        DatabaseEntry replacementData =
            new DatabaseEntry(replaceStr.getBytes("UTF-8"));
        cursor.putCurrent(replacementData);
    } catch (Exception e) {
        // Exception handling goes here
    } finally {
       // Make sure to close the cursor
       cursor.close();
    }

Note that you cannot change a record's key using this method; the key parameter is always ignored when you replace a record.

When replacing the data portion of a record, if you are replacing a record that is a member of a sorted duplicates set, then the replacement will be successful only if the new record sorts identically to the old record. This means that if you are replacing a record that is a member of a sorted duplicates set, and if you are using the default lexicographic sort, then the replacement will fail due to violating the sort order. However, if you provide a custom sort routine that, for example, sorts based on just a few bytes out of the data item, then potentially you can perform a direct replacement and still not violate the restrictions described here.

Under these circumstances, if you want to replace the data contained by a duplicate record, and you are not using a custom sort routine, then delete the record and create a new record with the desired key and data.

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