Tuần 6 - Ngày 3: DynamoDB Deep Dive

1. DynamoDB Capacity Modes

2. Secondary Indexes

3. DynamoDB Accelerator (DAX)

4. DynamoDB Transactions

TransactWriteItems:
- Up to 100 items
- Atomic (all or nothing)
- Consumes 2x WCU

TransactGetItems:
- Up to 100 items
- Consumes 2x RCU

Use cases:
- Financial transactions
- Gaming leaderboards
- Multi-item updates

5. Time To Live (TTL)

Auto-delete expired items:
- No extra cost
- Eventually deleted (within 48 hours)
- Define TTL attribute (epoch timestamp)

Use cases:
- Session data
- Temporary tokens
- Log cleanup

6. Patterns

Single Table Design

PK          | SK              | Data
------------+-----------------+--------
USER#123    | METADATA        | {name, email}
USER#123    | ORDER#001       | {order details}
USER#123    | ORDER#002       | {order details}
PRODUCT#A   | METADATA        | {product info}
ORDER#001   | PRODUCT#A       | {line item}

Benefits:
- Single query for all user data
- Reduced latency
- Cost optimization

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Tài liệu tham khảo chính thức

• Amazon DynamoDB Developer Guide
• DynamoDB Best Practices
• DynamoDB Global Tables
• DynamoDB Accelerator (DAX)

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Ngày tiếp theo: Data Analytics Services