Signature Description Parameters
template<typename ITR>
size_type
load_index(const ITR &begin const ITR &end);
It copies the data from iterators begin to end into the index column
Returns number of items loaded
ITR: Type of the iterator
template<typename ITR>
size_type
load_index(IndexVecType &&idx);
It moves the idx vector into the index column.
Returns number of items loaded