INTEGER for whole numbers

Integer literals in SQL are written as bare numbers without quotes. SQL uses quotes to distinguish strings from numbers: 42 (no quotes) is a number, while '42' (with quotes) is text. Integer Applications Integers are the most common type for IDs, counts, and any whole number data. Understanding storage size helps you choose between integer types for performance-sensitive tables. Integer types are hardware-accelerated in modern CPUs. Operations on integers run faster than equivalent operations on strings or decimal types, which matters at analytical scale.

About This Interactive Section

This section is part of the Data Types: Beginner 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 PostgreSQL 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.

How DataDriven Lessons Work

DataDriven combines four interview rounds (SQL, Python, Data Modeling, Pipeline Architecture) with adaptive difficulty and spaced repetition. Easy problems get harder as you improve. Weak concepts resurface until you master them. Your readiness score tracks progress across every topic interviewers test. Every lesson section ends with problems you solve by writing and running real code, not by picking multiple-choice answers.