I'm writing my own
Group by operator (non-hashed implementation) and I'm currently looking on a good data structure to store the result groups. There are two requirement in my mind: the table need to be efficiently expanded and the tuples within each group need to be sorted.
I carefully examined the implementation of standard
Group by (both hashed and sorted implementation), the closest I got is to leverage parts of the
TupleHashTable but before going through this plan, I need to make sure I'm not overlooking an existing data structure.