Edit File: 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 4. 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 4. 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 <span> <span><tt class="methodname">DBC->del()</tt>.</span> </span> </p> <p>For example:</p> <a id="c_cursor8"></a> <pre class="programlisting">#include <db.h> #include <string.h> ... DB *dbp; DBC *cursorp; DBT key, data; char *key1str = "My first string"; int ret; /* Database open omitted */ /* Initialize our DBTs. */ memset(&key, 0, sizeof(DBT)); memset(&data, 0, sizeof(DBT)); /* Set up our DBTs */ key.data = key1str; key.size = strlen(key1str) + 1; /* Get the cursor */ dbp->cursor(dbp, NULL, &cursorp, 0); /* Iterate over the database, deleting each record in turn. */ while ((ret = cursorp->get(cursorp, &key, &data, DB_SET)) == 0) { cursorp->del(cursorp, 0); } /* Cursors must be closed */ if (cursorp != NULL) cursorp->close(cursorp); if (dbp != NULL) dbp->close(dbp, 0);</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>
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