Explanation:V8 JavaScript engine became the default engine in 2.4 version. 2. Point out the correct statement :
A. The read phase takes a exclusive lock
B. The map-reduce operation is composed of many tasks
C. Prior to version 3, JavaScript code executed in a single thread
D. All of the mentioned
Answer:A
Explanation:V8 JavaScript engine became the default engine in 2.4 version. 2. Point out the correct statement :
A. The read phase takes a exclusive lock B. The map-reduce operation is composed of many tasks C. Prior to version 3, JavaScript code executed in a single thread D. All of the mentioned
Explanation:It includes reads from the input collection, executions of the map function, executions of the reduce function, writes to a temporary collection during processing, and writes to the output collection. 3. If the ______ field for mapReduce has the sharded value, MongoDB shards the output collection using the _id field as the shard key.