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<title>Berkeley DB: Db.set_append_recno</title>
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<h1>Db.set_append_recno</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public interface DbAppendRecno
{
public abstract void db_append_recno(Db db, Dbt data, int recno);
throws DbException;
}
public class Db
{
public void set_append_recno(DbAppendRecno db_append_recno)
throws DbException;
...
}
</pre></h3>
<h1>Description</h1>
<p>When using the <a href="../api_java/db_put.html#DB_APPEND">Db.DB_APPEND</a> option of the <a href="../api_java/db_put.html">Db.put</a> method,
it may be useful to modify the stored data based on the generated key.
If a callback method is specified using the
Db.set_append_recno method, it will be called after the record number
has been selected, but before the data has been stored.
The callback function must throw a <a href="../api_java/except_class.html">DbException</a> object to
encapsulate the error on failure. That object will be thrown to
caller of <a href="../api_java/db_put.html">Db.put</a>.
<p>The called function must take three arguments: a reference to the
enclosing database handle; the data <a href="../api_java/dbt_class.html">Dbt</a> to be stored; and the
selected record number. The called function may then modify the data
<a href="../api_java/dbt_class.html">Dbt</a>.
<p>The Db.set_append_recno method configures operations performed using the specified
<a href="../api_java/db_class.html">Db</a> handle, not all operations performed on the underlying
database.
<p>The Db.set_append_recno interface may not be called after the <a href="../api_java/db_open.html">Db.open</a>
interface is called.
<p>The Db.set_append_recno method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Class</h1>
<a href="../api_java/db_class.html">Db</a>
<h1>See Also</h1>
<a href="../api_java/db_list.html">Databases and Related Methods</a>
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