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<title>Berkeley DB Reference Guide: Storing records with a cursor</title>
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<td><dl><dt>Berkeley DB Reference Guide:<dd>Access Methods</dl></td>
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Storing records with a cursor
The <a href="../../api_c/dbc_put.html">DBcursor-&gt;put</a> method stores records into the database using a cursor. In
general, <a href="../../api_c/dbc_put.html">DBcursor-&gt;put</a> takes a key and inserts the associated data
into the database, at a location controlled by a specified flag.
There are several flags that you can set to customize storage:
 
<a href="../../api_c/dbc_put.html#DB_AFTER">DB_AFTER</a><ul compact><li>Create a new record, immediately after the record to which the cursor
refers.</ul>
<a href="../../api_c/dbc_put.html#DB_BEFORE">DB_BEFORE</a><ul compact><li>Create a new record, immediately before the record to which the cursor
refers.</ul>
<a href="../../api_c/dbc_get.html#DB_CURRENT">DB_CURRENT</a><ul compact><li>Replace the data part of the record to which the cursor refers.</ul>
<a href="../../api_c/dbc_put.html#DB_KEYFIRST">DB_KEYFIRST</a><ul compact><li>Create a new record as the first of the duplicate records for the
supplied key.</ul>
<a href="../../api_c/dbc_put.html#DB_KEYLAST">DB_KEYLAST</a><ul compact><li>Create a new record, as the last of the duplicate records for the supplied
key.</ul>
 
In all cases, the cursor is repositioned by a <a href="../../api_c/dbc_put.html">DBcursor-&gt;put</a> operation
to point to the newly inserted key/data pair in the database.
The following is a code example showing a cursor storing two data items
in a database that supports duplicate data items:
<blockquote><pre>int
store(dbp)
	DB *dbp;
{
	DBC *dbcp;
	DBT key, data;
	int ret;

	/*
	 * The DB handle for a Btree database supporting duplicate data
	 * items is the argument; acquire a cursor for the database.
	 */
	if ((ret = dbp-&gt;cursor(dbp, NULL, &dbcp, 0)) != 0) {
		dbp-&gt;err(dbp, ret, "DB-&gt;cursor");
		goto err;
	}

	/* Initialize the key. */
	memset(&key, 0, sizeof(key));
	key.data = "new key";
	key.size = strlen(key.data) + 1;

	/* Initialize the data to be the first of two duplicate records. */
	memset(&data, 0, sizeof(data));
	data.data = "new key's data: entry #1";
	data.size = strlen(data.data) + 1;

	/* Store the first of the two duplicate records. */
	if ((ret = dbcp-&gt;c_put(dbcp, &key, &data, DB_KEYFIRST)) != 0)
		dbp-&gt;err(dbp, ret, "DB-&gt;cursor");

	/* Initialize the data to be the second of two duplicate records. */
	data.data = "new key's data: entry #2";
	data.size = strlen(data.data) + 1;

	/*
	 * Store the second of the two duplicate records. No duplicate
	 * record sort function has been specified, so we explicitly
	 * store the record as the last of the duplicate set.
	 */
	if ((ret = dbcp-&gt;c_put(dbcp, &key, &data, DB_KEYLAST)) != 0)
		dbp-&gt;err(dbp, ret, "DB-&gt;cursor");

err:	if ((ret = dbcp-&gt;c_close(dbcp)) != 0)
		dbp-&gt;err(dbp, ret, "DBcursor-&gt;close");

	return (0);
}</pre></blockquote>
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