#include <db_cxx.h>
class DbMultipleKeyDataIterator
{
public:
DbMultipleKeyDataIterator(const Dbt &dbt);
bool next(Dbt &key, Dbt &data);
};
If either of the DB_MULTIPLE or DB_MULTIPLE_KEY flags were specified to the Db::get() or Dbc::get() methods, the data Dbt returned by those interfaces will refer to a buffer that is filled with data. Access to that data is through these classes.
The DbMultipleDataIterator class is used to iterate through data
returned using the
DB_MULTIPLE_KEY
flag from a database belonging to Btree or Hash access methods.
The constructor takes the The Dbt Handle returned by the call to Db::get() or Dbc::get() that used the DB_MULTIPLE_KEY flag.
All instances of the bulk retrieval classes may be used only once, and to traverse the bulk retrieval buffer in the forward direction only. However, they are nondestructive, so multiple iterators can be instantiated and used on the same returned data Dbt.
Parameters are:
dbt
The dbt parameter is a data The Dbt Handle returned by the call to Db::get() or Dbc::get() that used the DB_MULTIPLE_KEY flag.
The DbMultipleKeyDataIterator.next() method
returns the next data item in the original bulk retrieval buffer.
The DbMultipleKeyDataIterator.next() method
method returns false if no more data are available, and
true otherwise.
Parameters are:
key
The key parameter is a The Dbt Handle that will be filled in with a reference to a buffer, a size, and an offset that together yield the next data item in the original bulk retrieval buffer.
data
The data parameter is a The Dbt Handle that will be filled in with a reference to a buffer, a size, and an offset that together yield the next data item in the original bulk retrieval buffer.