Explanation:The inequality operators $nin and $ne are not very selective since they often match a large portion of the index. 10. An index cannot cover a query on a _______ collection when run against a mongos if the index does not contain the shard key.
A. vertical
B. sharded
C. horizontal
D. None of the mentioned
Answer:A
Explanation:The inequality operators $nin and $ne are not very selective since they often match a large portion of the index. 10. An index cannot cover a query on a _______ collection when run against a mongos if the index does not contain the shard key.
A. vertical B. sharded C. horizontal D. None of the mentioned
Explanation:MongoDB can both match the query conditions and return the results using only the index. Sanfoundry Global Education & Learning Series – MongoDB.