Explanation:MongoDB uses reader-writer locks that allow concurrent readers shared access to a resource, such as a database or collection, but give exclusive access to a single write operation. 5. Point out the wrong statement :
A. Beginning with version 3.0, MongoDB ships with the WiredTiger storage engine
B. Some global operations, typically short lived operations involving multiple databases, still require a global “instance-wide” lock
C. The MMAPv1 storage engine uses collection-level locking
D. None of the mentioned
Answer:A
Explanation:MongoDB uses reader-writer locks that allow concurrent readers shared access to a resource, such as a database or collection, but give exclusive access to a single write operation. 5. Point out the wrong statement :
A. Beginning with version 3.0, MongoDB ships with the WiredTiger storage engine B. Some global operations, typically short lived operations involving multiple databases, still require a global “instance-wide” lock C. The MMAPv1 storage engine uses collection-level locking D. None of the mentioned
Explanation:MongoDB operations can also yield locks between individual document modifications in write operations that affect multiple documents like update() with the multi parameter. 6. Which of the following keyword represents lock on collection ?