In network protocols, which layer does TCP/IP operate at?

The correct answer is C: Transport and Network Layers. TCP operates at Layer 4 (Transport) and IP at Layer 3 (Network) in the OSI model. Together they form the TCP/IP protocol suite.

What does the acronym ACID stand for in database transactions?

The correct answer is A: Atomicity, Consistency, Isolation, Durability. ACID properties ensure reliable database transactions: Atomicity (all-or-nothing), Consistency (valid state), Isolation (concurrent independence), Durability (permanent storage).

Which of the following is a non-relational database designed for handling unstructured data at scale?

The correct answer is A: MongoDB. MongoDB is a NoSQL document database that handles unstructured and semi-structured data efficiently, unlike relational databases like PostgreSQL, Oracle, and MySQL.

In SQL, what is the difference between INNER JOIN and LEFT JOIN?

The correct answer is B: INNER JOIN returns only matching rows; LEFT JOIN returns all rows from left table. INNER JOIN returns only rows with matches in both tables. LEFT JOIN returns all rows from the left table plus matching rows from the right table.

How many times will the loop execute? for(int i = 0; i < 5; i++)

The correct answer is B: 5 times. The loop initializes i to 0 and continues while i < 5. Values of i: 0, 1, 2, 3, 4. After i becomes 5, the condition is false, so the loop executes 5 times.

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Showing 61–65 of 65 questions

Q.61 Hard Database/SQL

In database normalization, what does the Boyce-Codd Normal Form (BCNF) address that 3NF might miss?

A Elimination of multivalued dependencies

B Removal of anomalies from composite candidate keys

C Prevention of circular foreign keys

D Ensuring data type consistency

Correct Answer: B. Removal of anomalies from composite candidate keys

Explanation:

BCNF handles edge cases in 3NF where anomalies can occur with composite candidate keys where determinants are not candidate keys themselves.

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Q.62 Hard Database/SQL

In distributed systems, what is a consensus algorithm primarily used for?

A Encrypting data

B Ensuring all nodes agree on a single value despite failures

C Compressing database files

D Load balancing across servers

Correct Answer: B. Ensuring all nodes agree on a single value despite failures

Explanation:

Consensus algorithms (like Raft, Paxos) enable distributed systems to reliably agree on state even with node failures.

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Q.63 Hard Database/SQL

What is the primary challenge of implementing ACID properties in distributed databases?

A Requires minimal network latency

B Network partitions, latency, and node failures make maintaining consistency difficult while ensuring availability

C Distributed systems automatically ensure ACID

D Only centralized databases can support ACID

Correct Answer: B. Network partitions, latency, and node failures make maintaining consistency difficult while ensuring availability

Explanation:

The CAP theorem shows it's impossible to guarantee all three: Consistency, Availability, and Partition tolerance simultaneously.

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Q.64 Hard Database/SQL

In AI/ML, what is the role of activation functions in neural networks?

A Encrypt network weights

B Introduce non-linearity enabling networks to learn complex patterns

C Increase training speed

D Reduce dataset size

Correct Answer: B. Introduce non-linearity enabling networks to learn complex patterns

Explanation:

Activation functions (ReLU, sigmoid, tanh) add non-linearity, allowing neural networks to approximate non-linear relationships.

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Q.65 Hard Database/SQL

In a sharded database architecture deployed on cloud infrastructure, which of the following represents the most critical challenge that must be addressed?

A Shard key selection and distribution skew

B Implementing full-text search across shards

C Eliminating all network latency between shards

D Converting all queries to read-only operations

Correct Answer: A. Shard key selection and distribution skew

Explanation:

Shard key selection determines data distribution and performance. Poor shard key choices lead to hotspots, uneven load distribution, and performance degradation across the sharded cluster.

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