What is data deduplication?

Updated May 15, 2026

Short answer

Data deduplication removes duplicate records from datasets.

Deep explanation

It improves storage efficiency and data accuracy by identifying and eliminating repeated entries using hashing or comparison logic.

Real-world example

Removing duplicate customer entries in CRM systems.

Common mistakes

  • Removing valid repeated events mistakenly.

Follow-up questions

  • What techniques detect duplicates?
  • Why is deduplication important?

More Data Processing interview questions

View all →