ef-core-advanced-patterns

N+1 query problems occur when loading related entities triggers additional database calls. Use eager loading with Include(), explicit loading, or split queries to fetch related data efficiently in fewer round trips, reducing query overhead and improving application performance.

Eager loading fetches related data upfront with Include(); explicit loading retrieves data on demand using Load(); lazy loading automatically loads data when accessed. Each suits different scenarios: eager for known relationships, explicit for conditional loading, and lazy for transparent but unpredictable access patterns.

Use AsNoTracking on read-only queries where you don't need change tracking, reducing memory overhead and improving throughput. It's ideal for reporting, bulk reads, and high-volume scenarios where entity state management adds unnecessary cost without providing value.

Split queries break multi-collection joins into separate queries to avoid cartesian explosion, where result sets multiply unexpectedly. Use AsSplitQuery() to execute multiple focused queries instead of one complex join, preserving data accuracy and query efficiency.

EF Core leverages PostgreSQL features including array types, JSON operators, and native pagination for optimized queries. These enable specialized patterns aligned with PostgreSQL strengths, supporting scalable read-heavy workloads and complex data structures.

Optimistic concurrency uses version tokens or timestamps to detect conflicts when multiple clients modify the same entity. Configure concurrency tokens with HasConcurrencyToken(), catch DbUpdateConcurrencyException on SaveChanges(), and implement retry logic to handle contention safely.