Column

Lesson in the SQL Roadmap · Stage 7: Subqueries

Last updated 14 September 2026

What is Column?

In SQL, columns are used to categorize the data in a table. A column serves as a structure that stores a specific type of data (ints, str, bool, etc.) in a table. Each column in a table is designed with a type, which configures the data that it can hold. Using the right column types and size can help to maintain data integrity and optimize performance.

Study this in the interactive course See the whole SQL roadmap

Free resources to learn Column

ArticleColumn Types - PostgreSQL

Column: common questions

Can I learn Column in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Column in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Column tutorial for beginners?

It is lesson 47 of 112 in the free SQL roadmap, in stage 7, Subqueries. If you are new to SQL, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.