4. SELECT All Data

The SELECT Statement

The SELECT statement is the most fundamental SQL command. It retrieves data from database tables.

SELECT * Syntax

The asterisk * means "all columns":

1SELECT * FROM table_name;

Example: Get All Students

1SELECT * FROM students;

Result

Breaking Down the Query

• SELECT - Command to retrieve data
• * - All columns
• FROM - Specifies the source
• students - Table name

When to Use SELECT *

Good for:

• Quick data exploration
• Small tables
• Testing queries

Avoid when:

• Large tables (performance)
• Production code (specify columns)
• Joining tables (column confusion)

Best Practice

In production, specify columns explicitly:

1-- Better for production
2SELECT name, age, course FROM students;

This makes queries faster and more maintainable.