**Why Delta matters**: Parquet + transaction log = mutable lakehouse with reliability. **ACID**: Transaction log (_delta_log/) records commits; concurrent reads/writes serialized. **Time travel**: Query by version or timestamp; `VERSION AS OF n` or `TIMESTAMP AS OF '...'`. **Streaming**: Read/write as stream; merge support; exactly-once with checkpoint. **Scalability trade-offs**: Log grows; VACUUM removes old files. Time travel retention = storage....
The complete answer continues with detailed implementation patterns, architectural trade-offs, and production-grade considerations. It covers performance optimization strategies, common pitfalls to avoid, and real-world examples from companies like Kaseya. The answer also includes follow-up discussion points that interviewers commonly explore.
Continue Reading the Full Answer
Unlock the complete expert answer with code examples, trade-offs, and pro tips - plus 1,863+ more.
Or upgrade to Platform Pro - $39
Engineers who used these answers got offers at
AmazonDatabricksSnowflakeGoogleMeta
According to DataEngPrep.tech, this is one of the most frequently asked Spark/Big Data interview questions, reported at 1 company. DataEngPrep.tech maintains a curated database of 1,863+ real data engineering interview questions across 7 categories, verified by industry professionals.