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Primary Keys | Populating a Database
Introduction to SQL
course content

Course Content

Introduction to SQL

Introduction to SQL

1. Getting Started
3. Sorting Data
4. Populating a Database
5. Updating & Deleting Data

book
Primary Keys

A primary key is a column in a table which:

  1. Has a unique value for each row (no duplicate values);
  2. Cannot contain an empty / null value for any row.

A column can be marked as a primary key using the PRIMARY KEY keyword, inside the CREATE statement while creating the respective table.

Demonstration:

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Section 4. Chapter 8
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