Optimized-External-Sorting-Algorithm-for-Database-Records/notes at main · apoorva1999/Optimized-External-Sorting-Algorithm-for-Database-Records · GitHub

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TODO

- row()
- generateData
- scan


Every plan has -
    datamember
    - plan* as input
    - iterator* as init
    methods
    -

Every iterator has
    - Iterator* as input

    methods
    - next
    - free


ScanPlan
    - _count = total number of rows
    - name
--------------
WitnessIterator
    - WitnessPlan as _plan
    - ScanIterator as _input
    - _rows = 0
SortIterator
    - produced 0
    - consumed 0
    - WitnessIterator as _input
    - SortPlan as _plan
    - starts next chain in its constructor

FilterIterator
    - produced 0
    - consumed 0

ScanIteraor
    - _count = 0 (number of rows scanned currently)
    - _plan = ScanPlan


Witness -> Sort -> Witness -> Filter -> Scan

init run

calls next of witness, which calls next of sort that it