Which operator within the $lookup stage specifies the field in the 'joined' collection that should match the 'localField'?
foreignField
as
from
localField
How can you ensure optimal memory allocation for the MongoDB WiredTiger storage engine?
Manually configure the size of the WiredTiger internal cache
Regularly compact the database to reclaim unused space
Set the --noprealloc flag during mongod startup
--noprealloc
Disable journaling for improved write performance
The 'Attribute Pattern' in MongoDB schema design is most suitable for...
Optimizing queries that require aggregation of data
Storing arrays of simple, non-repeating values
Modeling relationships between documents in different collections
Representing historical data with frequent changes
What is the minimum number of nodes required to set up a MongoDB replica set?
3
2
1
7
What role does an arbiter node play in a MongoDB replica set?
It manages backups and restores for the replica set.
It participates in elections but doesn't store data.
It processes read and write operations like other nodes.
It stores a copy of the data for redundancy.
Which of these is a potential drawback of embedding documents in MongoDB?
Inability to represent one-to-many relationships effectively
Data duplication if not carefully managed
Reduced performance when retrieving deeply nested data
Increased complexity in querying related data
When are transactions in MongoDB typically considered essential?
For improving the performance of individual queries.
When ACID properties are crucial, such as when multiple operations need to succeed or fail together to maintain data consistency.
For all database operations to guarantee data integrity.
When performing read-only operations to ensure consistent snapshots of data.
What is the primary purpose of the MongoDB In-Memory Storage Engine?
High-speed data analysis
Long-term data persistence
Reducing storage costs
Full-text search indexing
In a compound index {field1: 1, field2: -1}, what does the '-1' signify for 'field2'?
Descending order sort.
Ascending order sort.
Exclude 'field2' from the index.
Mark 'field2' as a sparse field.
Choosing an inappropriate shard key can lead to which of the following issues?
Reduced query performance
Decreased storage requirements
Simplified data backup processes
Improved data security