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Manuals / SQL / Chapter 2

A · Query · beginner · Week 1 · Chapter 2 of 12

SELECT basics — reading rows

Every query starts with SELECT. Name columns explicitly in production. DISTINCT removes duplicates. Aliases rename columns or tables.

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Step 1 of 3

Basic SELECT

SELECT col1, col2 FROM table. Avoid SELECT * in production — it hides schema changes and fetches unnecessary data.

Basic SELECTDrag stickies · tap for tips
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Example

SELECT id, name, email
FROM users;

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SQLBolt lesson 1. Save query as queries/01_select.sql.

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Chapter learning outcomes
  • SELECT columns
  • DISTINCT
  • Column aliases
  • FROM and table names

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Side quest

Column audit

For each table: list columns, types, and one sample value.