String-to-Date and Date-to-String

Concepts covered: sqlCast

Timestamp types are the type-casting area that catches the most engineers. The same logical value (a specific moment in time) can be stored as TIMESTAMP (no timezone, just date and time), TIMESTAMPTZ (an absolute moment with timezone awareness), or DATETIME (engine-specific semantics). Casting between them is not always lossless; conventions differ across engines. The three timestamp flavors TIMESTAMP (without timezone): stores a date and time, no zone information. When displayed, the engine assumes either UTC or the session zone, depending on the engine. TIMESTAMPTZ (with timezone): stores an absolute moment; on display, converts to the session's timezone. The internal representation is usually UTC. DATETIME: BigQuery-specific; like TIMESTAMP but with different defaults. State this when d

About This Interactive Section

This section is part of the Type Casting: Intermediate lesson on DataDriven, a free data engineering interview prep platform. Each section includes explanations, worked examples, and hands-on code challenges that execute in real time. SQL queries run against a live database. Python runs in a sandboxed Docker container. Data modeling problems validate against interactive schema canvases. All content is framed around what data engineering interviewers actually test at companies like Meta, Google, Amazon, Netflix, Stripe, and Databricks.

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