Database Indexes
An index is a data structure that speeds up data retrieval at the cost of storage and write performance.
0:00
0% complete
LearnStep 1 of 2
Index Basics
Learning Objectives
- •Understand indexing concept
- •Learn index types
Lesson Outline
LearnStep 1/2
Index Basics
Index Structure
Index Types
| Type | Best For | Example |
|---|---|---|
| B-Tree | Range queries, equality | Most common |
| Hash | Equality only | WHERE id = 5 |
| Full-text | Text search | Search engines |
| Bitmap | Low cardinality | Gender, Status |
Creating Indexes
sql
Trade-offs
- Pros: Faster SELECT queries
- Cons: Slower INSERT/UPDATE/DELETE, extra storage