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Difference between var, val, and def in Scala

General/Otherhard0.4 min readPremium
Frequency
Low
Asked at 1 company
Category
243
questions in General/Other
Difficulty Split
151E|43M|49H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Matrix
Key Concepts Tested
spark
Expert AnswerPremium
71 wordsInterview-ready
**Why It Matters for Data Engineering**: Immutability reduces bugs in distributed pipelines; def enables lazy/computed values. **var**: Mutable, reassignable. Use sparingly—loops, accumulators. Risk: shared state in concurrent code. **val**: Immutable binding; computed once at definition. Preferred for RDDs/DataFrames—avoids accidental reassignment. **def**: Method; re-evaluated each call....
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