Lesson 4.1 Introduction to Databases
A database is an organized system that stores, manages, and retrieves data efficiently. Data is stored in tables, each containing rows (records) and columns (fields).
Key Concepts
- Table: A structured collection of related data
- Row (Record): A single data entry
- Column (Field): A type of data stored (e.g., name, age, salary)
- Primary Key: Unique identifier for each row
- Foreign Key: Connects two related tables
Why SQL Matters
SQL (Structured Query Language) is the standard language for querying and managing databases used in analytics.