Snowflake Data Engineer Interview Questions

Temporary tables exist only for the current session, transient tables reduce storage overhead by limiting recovery features, and permanent tables retain the full set of Snowflake durability features. I would choose based on lifecycle, recovery needs, and whether the data is truly disposable. The decision is mostly about governance and retention, not just convenience.

I would use roles, masking policies, row access policies, and secure views to control who can see what. The main principle is to enforce policy at the platform level so security does not depend on every downstream query behaving correctly. Good security design also makes auditing and governance easier.

A secure view protects the underlying logic and helps prevent unauthorized users from inferring sensitive details about the data model. I would use it when I want to share curated data while limiting metadata exposure. It is especially useful in governed data-sharing scenarios.

Snowflake lets organizations share live data without copying it into another physical system. That means consumers can query shared data directly under controlled permissions, which reduces duplication and data movement. It is powerful because access can be granted centrally while the data remains governed by the provider.

I would store it in VARIANT when flexibility is useful, then extract fields into relational columns where query patterns need consistency and speed. This hybrid approach gives me both schema flexibility and analytical structure. The trade-off is that leaving everything nested can make downstream querying harder.