Big Data Analytics MCQs

The JVM invokes a main entry point to start the program.
Build tools package the compiled classes and dependencies.

Failures and speculation can cause task attempts to repeat.
Idempotence prevents duplicate side effects from corrupting results.

Preemption enforces queue guarantees or priorities.
It can reduce efficiency if containers are killed frequently.

A var can be reassigned after declaration.
Functional Scala style generally prefers val when possible.

Sets support membership tests and set operations.
Duplicate insertions do not create repeated elements.

Concurrent tasks cannot overwrite an immutable value's state.
This reduces race conditions and makes reasoning about distributed code easier.

Intermediate data can be large and temporary.
Compression often saves more transfer time than it costs in CPU.

A request must fit the available resources on a node.
Large indivisible requests can wait while smaller resource fragments remain unused.

Methods are introduced with def and can accept parameter lists.
Their return type may be inferred or written explicitly.

Each key maps to a value within the collection.
Immutable Map is the default import in standard Scala.

Lazy initialization postpones work until the value is needed.
After the first evaluation, the result is cached.

Unsplittable compressed files may be assigned to one mapper.
Splittability preserves input parallelism.