| Current Path : /usr/share/doc/db4-devel-4.7.25/gsg/JAVA/ |
| Current File : //usr/share/doc/db4-devel-4.7.25/gsg/JAVA/DeleteEntryWCursor.html |
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Deleting Records Using Cursors</title>
<link rel="stylesheet" href="gettingStarted.css" type="text/css" />
<meta name="generator" content="DocBook XSL Stylesheets V1.62.4" />
<link rel="home" href="index.html" title="Getting Started with Berkeley DB" />
<link rel="up" href="Cursors.html" title="Chapter 9. Using Cursors" />
<link rel="previous" href="PutEntryWCursor.html" title="Putting Records Using Cursors" />
<link rel="next" href="ReplacingEntryWCursor.html" title="Replacing Records Using Cursors" />
</head>
<body>
<div class="navheader">
<table width="100%" summary="Navigation header">
<tr>
<th colspan="3" align="center">Deleting Records Using Cursors</th>
</tr>
<tr>
<td width="20%" align="left"><a accesskey="p" href="PutEntryWCursor.html">Prev</a> </td>
<th width="60%" align="center">Chapter 9. Using Cursors</th>
<td width="20%" align="right"> <a accesskey="n" href="ReplacingEntryWCursor.html">Next</a></td>
</tr>
</table>
<hr />
</div>
<div class="sect1" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both"><a id="DeleteEntryWCursor"></a>Deleting Records Using Cursors</h2>
</div>
</div>
<div></div>
</div>
<p>
To delete a record using a cursor, simply position the cursor to the
record that you want to delete and then call
</p>
<p>For example:</p>
<a id="java_cursor8"></a>
<pre class="programlisting">package db.GettingStarted;
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);
// Count the number of records using the given key. If there is only
// one, delete that record.
if (cursor.count() == 1) {
System.out.println("Deleting " +
new String(theKey.getData(), "UTF-8") +
"|" +
new String(theData.getData(), "UTF-8"));
cursor.delete();
}
} catch (Exception e) {
// Exception handling goes here
} finally {
// Make sure to close the cursor
cursor.close();
}</pre>
</div>
<div class="navfooter">
<hr />
<table width="100%" summary="Navigation footer">
<tr>
<td width="40%" align="left"><a accesskey="p" href="PutEntryWCursor.html">Prev</a> </td>
<td width="20%" align="center">
<a accesskey="u" href="Cursors.html">Up</a>
</td>
<td width="40%" align="right"> <a accesskey="n" href="ReplacingEntryWCursor.html">Next</a></td>
</tr>
<tr>
<td width="40%" align="left" valign="top">Putting Records Using Cursors </td>
<td width="20%" align="center">
<a accesskey="h" href="index.html">Home</a>
</td>
<td width="40%" align="right" valign="top"> Replacing Records Using Cursors</td>
</tr>
</table>
</div>
</body>
</html>
Copyright 2K16 - 2K18 Indonesian Hacker Rulez
;?>)