1. Explain how to split the hybrid hash-join operator into sub-operators to model pipelining. Also explain how this split is different from the split for a hash-join operator.

2. Write pseudocode for an iterator that implements a version of the sort–merge algorithm where the result of the final merge is pipelined to its consumers. Your pseudocode must define the standard iterator functions open(), next(), and close(). Show what state information the iterator must maintain between calls