MongoDB is an example of a document$-$store database. Is it possible to have duplicate

entries? Is that a good thing to allow or not?

Consider this fragment:

db$.$createCollection$($myq$)$

db$.$myq$.$insert $(\{$name: $$CS$,$ num: $7330\})$

db$.$myq$.$insert $(\{$name: $$CS$,$ num: $7330\})$

db$.$myq$.$find$()$

$//$