Explanation:The query scans the index and not the collection. 3. A prefix of a _______ index is a subset that consists of one or more keys at the start of the index key pattern.
A. unique
B. primary
C. compound
D. None of the mentioned
Answer:A
Explanation:The query scans the index and not the collection. 3. A prefix of a _______ index is a subset that consists of one or more keys at the start of the index key pattern.
A. unique B. primary C. compound D. None of the mentioned
Explanation:If the sort keys correspond to the index keys or an index prefix, MongoDB can use the index to sort the query results. 4. Sort operations that do not use an index will abort when they use _______ megabytes of memory.