MongoDB Interview Questions and Answers
Question - 71 : - How to do Journaling in MongoDB?
Answer - 71 : -
We save the write operations in the memory while journaling is taking place. The on-disk journal files are dependable for the reason that journal writers are usual. In the DB path, MongoDB designs a journal subdirectory.
Question - 72 : - How does MongoDB provides concurrency?
Answer - 72 : -
MongoDB utilizes the reader-writer locks, enabling concurrent readers to access any supply such as collection or database though it provides private access to individual writers.
Question - 73 : - Explain Sharding and Aggregation in MongoDB?
Answer - 73 : -
- Aggregation: Aggregations are the activities that handle the data records and give the record results.
- Sharding: Sharding means storing the data on multiple machines.
Question - 74 : - What is the importance of profiler in MongoDB?
Answer - 74 : -
MongoDB contains the database profiler that shows the performance characteristics of every operation against the database. Through the profiler, we can identify the queries that are slower than they should be and use this data to determine when we require an index.
Question - 75 : - Define Collection?
Answer - 75 : -
The collection is a set of MongoDB documents.
Question - 76 : - Explain Aggregation Pipeline?
Answer - 76 : -
The aggregation Pipeline acts as a framework to perform aggregation tasks. We use this pipeline for transforming the documents into aggregated results.
Question - 77 : - Explain MapReduce?
Answer - 77 : -
MapReduce is a standard multi-phase data aggregation modality that we use to process the data quantities.
Question - 78 : - Explain Splitting?
Answer - 78 : -
Splitting is the background process that we use to store chunks from increasing too large.
Question - 79 : - What is the purpose of the save() method?
Answer - 79 : -
We use the save() method for replacing the existing documents with new documents.
Question - 80 : - What is the purpose of the DB command?
Answer - 80 : -
We use the “DB” command to get the name of the presently selected database.