Understanding Database Design

Good database design is crucial for application performance and maintainability.

Database Normalization

Normalization eliminates redundancy and ensures data integrity:

• First Normal Form (1NF): Atomic values only
• Second Normal Form (2NF): No partial dependencies
• Third Normal Form (3NF): No transitive dependencies

Relationships

Types of Relationships

1. One-to-One
2. One-to-Many
3. Many-to-Many

Copy
1-- Example: Creating a foreign key relationship
2CREATE TABLE orders (
3    id INT PRIMARY KEY,
4    user_id INT,
5    FOREIGN KEY (user_id) REFERENCES users(id)
6);

Indexing Strategy

Indexes improve query performance but have trade-offs:

• Use indexes on frequently queried columns
  • Primary keys (automatic)
  • Foreign keys
• Avoid over-indexing
  • Slows down writes
  • Increases storage

ACID Properties

Property	Description
Atomicity	All or nothing
Consistency	Valid state transitions
Isolation	Concurrent execution
Durability	Permanent changes

"Weeks of coding can save you hours of planning."

• Unknown

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Best Practices

Always consider:

• Query patterns
• Data volume growth
• Premature optimization Strategic optimization

Pro tip: Profile your queries before optimizing! Use EXPLAIN to understand query execution.

For more information, check out Database Design Principles.