So combining @JorizovdZ and @rocco_sprmnt21’s solution here and @bkamins solution here thus far I think the best way to combine a new DataFrame
with an existing Arrow
file ensuring unique values without bringing the Arrow
file into memory would be something like
database = "filepath"
Arrow.write(database ,dataDF, file = false) # when saving the dataDF as arrow file - keyword file has to be set to false
dataDF = DataFrame(Arrow.Table(database))
NewDF = antijoin(NewDF, dataDF , on = intersect(names(NewDF), names(DataDF))
Arrow.append (database, NewDF)