Azure Cosmos DB Developer Specialty (DP-420) Practice Plan¶

Overview¶

Exam: DP-420 - Azure Cosmos DB Developer Specialty Timeline: 8-10 weeks Study Time: 8-12 hours per week Difficulty: Specialty/Associate level

This practice plan targets developers who design, implement, and monitor Azure Cosmos DB solutions.

Prerequisites¶

Experience with Azure and NoSQL databases
Proficiency in C#, Python, or Java
Understanding of data modeling concepts
Active Azure subscription with Cosmos DB access

Study Resources¶

Official Microsoft Learn DP-420 Path (FREE)
Cosmos DB Documentation
Complete Azure Study Resources
README.md in this directory

Week-by-Week Breakdown¶

Week 1-2: Data Models and Cosmos DB Fundamentals¶

Learning Objectives: - Master NoSQL data modeling - Understand Cosmos DB architecture - Learn partitioning strategies - Explore different APIs

Daily Tasks: - [ ] Study NoSQL vs relational data modeling - [ ] Learn Cosmos DB request units (RUs) - [ ] Understand partitioning and partition keys - [ ] Explore Core (SQL) API - [ ] Learn MongoDB API - [ ] Study Cassandra and Gremlin APIs - [ ] Practice data model design patterns

Hands-on Labs: - [ ] Create Cosmos DB account with different APIs - [ ] Design partition key for sample applications - [ ] Model one-to-many relationships - [ ] Implement embedding vs referencing patterns - [ ] Calculate RU consumption for operations - [ ] Practice with Data Explorer

Practice Questions: - [ ] Complete 40-50 questions on data modeling

Week 3-4: Implementing Data Models and Distribution¶

Learning Objectives: - Master container and item operations - Implement indexing policies - Configure global distribution - Understand consistency levels

Daily Tasks: - [ ] Learn CRUD operations with SDKs - [ ] Study indexing policies and optimization - [ ] Understand consistency levels (Strong, Bounded, Session, etc.) - [ ] Configure multi-region writes - [ ] Implement conflict resolution - [ ] Learn about hierarchical partition keys - [ ] Practice bulk operations

Hands-on Labs: - [ ] Implement CRUD with .NET/Python SDK - [ ] Configure custom indexing policy - [ ] Set up geo-replication - [ ] Test different consistency levels - [ ] Implement bulk insert operations - [ ] Configure automatic failover - [ ] Monitor cross-region latency

Practice Questions: - [ ] Complete 50-60 questions on implementation

Week 5-6: Integration and Query Optimization¶

Learning Objectives: - Master SQL queries in Cosmos DB - Implement change feed - Integrate with Azure services - Optimize query performance

Daily Tasks: - [ ] Learn SQL query syntax for Core API - [ ] Implement change feed processor - [ ] Integrate with Azure Functions - [ ] Connect to Azure Search - [ ] Implement stored procedures - [ ] Create user-defined functions (UDFs) - [ ] Optimize queries with query metrics

Hands-on Labs: - [ ] Write complex SQL queries - [ ] Implement change feed with Functions - [ ] Create stored procedures and triggers - [ ] Build aggregation pipelines - [ ] Optimize queries using metrics - [ ] Implement continuation tokens for pagination - [ ] Connect Cosmos DB to Synapse Analytics

Practice Questions: - [ ] Complete 40-50 questions on integration

Week 7: Performance Optimization¶

Learning Objectives: - Optimize throughput provisioning - Implement caching strategies - Monitor and troubleshoot performance - Manage costs

Daily Tasks: - [ ] Learn autoscale vs manual throughput - [ ] Implement caching with Redis - [ ] Monitor with Application Insights - [ ] Analyze query execution plans - [ ] Optimize partition key selection - [ ] Implement retry policies - [ ] Calculate and optimize costs

Hands-on Labs: - [ ] Configure autoscale throughput - [ ] Implement direct mode connectivity - [ ] Set up monitoring dashboards - [ ] Analyze slow queries - [ ] Implement connection pooling - [ ] Configure retry policies - [ ] Optimize for hot partitions

Practice Questions: - [ ] Complete 40-50 questions on optimization

Week 8: Maintenance and Security¶

Learning Objectives: - Implement security best practices - Configure backup and restore - Manage access control - Implement compliance

Daily Tasks: - [ ] Configure firewall rules - [ ] Implement managed identities - [ ] Set up Key Vault integration - [ ] Configure RBAC - [ ] Learn backup and restore options - [ ] Implement data encryption - [ ] Configure private endpoints

Hands-on Labs: - [ ] Configure network security - [ ] Implement managed identity access - [ ] Store connection strings in Key Vault - [ ] Perform point-in-time restore - [ ] Configure continuous backup - [ ] Set up private link - [ ] Implement resource tokens

Practice Questions: - [ ] Complete 40-50 questions on maintenance

Week 9-10: Practice and Review¶

Daily Tasks: - [ ] Review all exam domains - [ ] Take 3-4 full practice exams - [ ] Build end-to-end Cosmos DB application - [ ] Review weak areas - [ ] Practice coding scenarios - [ ] Review best practices - [ ] Final exam preparation

Practice Focus: - [ ] Practice exam 1 score: _% - [ ] Practice exam 2 score: % - [ ] Practice exam 3 score: __% - [ ] Comprehensive review completed - [ ] Exam scheduled

Key Topics Checklist¶

Data Models (35-40%)¶

Data Distribution (5-10%)¶

Integration (5-10%)¶

Optimization (15-20%)¶

Maintenance (25-30%)¶

Hands-on Lab Checklist¶

Build multi-tenant application with Cosmos DB
Implement change feed processor
Create globally distributed app
Optimize queries with indexing
Implement caching layer
Build event-driven architecture
Monitor and troubleshoot issues

Additional Resources¶

Success Strategy: Focus on hands-on development with Cosmos DB SDKs and understanding NoSQL data modeling patterns.