Delta or Iceberg?

Concepts: paTableFormats

This stops being a feature comparison and becomes a vendor strategy question. The interviewer wants to hear how you'd make this choice for an organization, not a project. Compute Coupling and Lock-In Delta Lake is open-source, but the optimizations that make it fast - Z-ordering, liquid clustering, predictive I/O - are proprietary to its parent platform. Open-source Delta on vanilla Spark is 2-5x slower on complex queries than the commercial runtime. This is intentional: the vendor monetizes the compute layer, not the format. If you adopt Delta, you're not locked into the format (it's open), but you are economically locked into the vendor's compute for competitive performance. When the interviewer asks why you'd choose Iceberg over Delta, the answer that signals strategic thinking is: