Aggregation groups values from different documents and performs operations on the data to return a single result. There are 3 ways in which MongoDB performs aggregation –
Aggregation pipeline
Map-reduce function
Single purpose aggregation methods
Posted Date:- 2021-08-31 07:27:15
Can the old files in the ‘moveChunk’ directory be removed?
What happens when a Shard is down or slow when querying?
What happens when a document is updated on a chunk that is being migrated?
When will data be on more than one Shard?
What is the importance of GridFS and Journaling?
Does MongoDB write to disk automatically or slowly?
How does concurrency affect primary replica set?
State the difference between find() and limit() method.
Explain aggregation in MongoDB.
What are MongoDB’s data models?
How do you see the Mongos connection?
On a high level, compare SQL databases and MongoDB.
How does MongoDB handle transactions and locks?
Explain the role of profiler in MongoDB.
What are the similarities and differences between sharding and replication in MongoDB?
What are the various languages that MongoDB supports?
What is an ACID transaction? Does MongoDB support it?
Explain the significance of the covered query?
Why MongoDB is the best NoSQL database?
Explain about Indexes in MongoDB?
How long does replica set failover take?
How do I do transactions/locking?
Does an update fsync to disk immediately?
In what ways is MongoDB better than MySQL? Explain.
How are sharding and replication similar to each other in MongoDB, and how are they different?
Name the 2 storage engines using MongoDB?
What is a covered query and why is it important?
Name the default index created for a new collection.
How can you query real-time MongoDB data?
What is ObjectId? How is it structured?
How are constraints managed in MongoDB?
How do you perform CRUD operations in MongoDB?
MongoDB is called a schema-less database. Is it true? How to create the schema in MongoDB?
How is data stored in MongoDB?
What specifically is a collection in MongoDB?
Differentiate MongoDB and MySQL?
What type of NoSQL database MongoDB is?
What is a storage engine? What are the different types of storage engines available in MongoDB?
What type of NoSQL database is MongoDB?