Question:- Compare MongoDB with Couchbase and CouchbaseDB.
Answer:- Although MongoDB, Couchbase, and Couchbase DB are common in many ways, still they are different in the case of necessities for the execution of the model, crossing points, storage, duplications, etc.
Question:- When do we use a namespace in MongoDB?
Answer:- During the sequencing of the names of the database and the collection, the namespace is used.
Question:- If you remove an object attribute, is it deleted from the database?
Answer:- Yes, it is deleted. Hence, it is better to eliminate the attribute and then save the object again.
Question:- If you remove an object attribute, is it deleted from the database?
Answer:- Yes, it is deleted. Hence, it is better to eliminate the attribute and then save the object again.
Question:- How can we move an old file into the moveChunk directory?
Answer:- Once the functions are done, the old files are converted to backup files and moved to the moveChunk directory at the time of balancing the slices.
Question:- Explain the situation when an index does not fit into RAM.
Answer:- When an index is too huge to fit into RAM, then MongoDB reads the index, which is faster than reading RAM because the indexes easily fit into RAM if the server has got RAM for indexes, along with the remaining set.
Question:- How does MongoDB provide consistency?
Answer:- MongoDB uses the reader–writer locks, allowing simultaneous readers to access any supply like a database or a collection but always offering private access to single writes.
Question:- Why is MongoDB not chosen for a 32-bit system?
Answer:- Mongo DB is not considered as a 32-bit system because for running the 32-bit MongoDB, with the server, information and indexes require 2 GB. That is why it is not used in 32-bit devices.
Question:- How does Journaling work in MongoDB?
Answer:- Write operations are saved in memory while journaling is going on. The on-disk journal files are really dependable for the reason that the journal writes are habitual. Inside dbPath, a journal subdirectory is designed by MongoDB.
Question:- How can you isolate the cursors from intervening with the write operations?
Answer:- The snapshot() method is used to isolate the cursors from intervening with writes. This method negotiates the index and makes sure that each query comes to any article only once.
Question:- Define MongoDB.
Answer:- It is a document-oriented database that is used for high availability, easy scalability, and high performance. It supports the dynamic schema design.
Question:- Explain the replica set.
Answer:- It is a group of mongo instances that maintains the same dataset. Replica sets provide redundancy and high availability and are the basis for all production deployments.
Question:- What are the key features of MongoDB?
Answer:- There are three main features of MongoDB: • Automatic scaling • High performance • High availability
Question:- What is CRUD?
Answer:- MongoDB provides CRUD operations: Create Read Update Delete