Question

An index prefix is a subset of a ______ index, consisting of one or more keys starting from the beginning of the index.

(a) Hashed

(b) Unique

(c) Sparse

(d) Compound

I had been asked this question in class test.

The query is from Index Types topic in section Index/Indexing Concepts of MongoDB

Answer 1

Right answer is (d) Compound

The best I can explain: With index intersection, MongoDB can use an intersection of either the entire index or the index prefix.