Claim: Data independence refers to the decoupling of the logical view of data from its physical storage. Answer: ✅ True Why: Data independence means you can change physical storage (files, indexes, partitions, hardware) without changing the logical schema seen by users/apps.
Claim: Big Data technologies primarily address the growing discrepancy between storage capacity, throughput, and latency. Answer: ✅ True Why: We can store tons of data cheaply (capacity grows fast), but moving/processing it (throughput) and accessing it quickly (latency) is harder. Big Data systems (distributed storage + parallel compute) are built around this bottleneck.
Claim: Renaming columns in SQL does not have an equivalent relational algebra operator.
Answer: ❌ False
Why: Relational algebra has the rename operator ρ (rho), which can rename relations and attributes. SQL AS corresponds to ρ.
Claim: Big Data systems often discard normalization to improve scalability and performance. Answer: ✅ True Why: In distributed systems, joins are expensive (network + shuffle). Denormalization trades redundancy for fewer joins and better read/write performance at scale.
Task: Select artist name with albums released in the most different countries (tie-breaker: alphabetical), excluding "Various Artists".
Answer: ✅ Technotronic
How to think about it:
"Various Artists"