right so memory is defined here https://github.com/libbitcoin/libbitcoin-database/blob/master/include/bitcoin/database/memory/memory.hpp#L33-L43
/// This interface defines remap safe unrestricted access to a memory map.
class BCD_API memory
{
public:
typedef std::shared_ptr<memory> ptr;
/// Get the address indicated by the pointer.
virtual uint8_t* buffer() = 0;
/// Increment the pointer the specified number of bytes within the record.
virtual void increment(size_t value) = 0;
};
