neo-dotnet-ef-core

name	neo-dotnet-ef-core
description	Use this skill when the task involves Entity Framework Core models, DbContext, migrations, LINQ queries, change tracking, database providers, performance tuning, or data access review in .NET projects.
compatibility	Supports .NET 6.0 through 10.0 environments. Compatible with SQL Server, PostgreSQL, MySQL, and SQLite.
metadata	{"version":"1.0.0","category":"Framework"}

EF Core Expert Skill

Trigger On

• The user requests database modeling, writing Linq queries, or handling database migrations.
• The project contains a DbContext class or references the Microsoft.EntityFrameworkCore package.
• There is a need to optimize database access performance or solve N+1 query problems.
• The task involves complex data relationship design (one-to-many, many-to-many, inheritance mapping).

Workflow

1. Perceive (Model Awareness):
   • Check .csproj to identify the EF Core version and database provider.
   • Analyze DbContext and entity configurations to confirm whether the Fluent API pattern is adopted.
   • Identify the current state of Migrations.
2. Reason (Planning Phase):
   • Evaluate whether queries need .AsNoTracking() or .AsSplitQuery().
   • Determine whether custom interceptors are needed to handle audit fields.
   • Evaluate whether to use ExecuteUpdate/Delete (.NET 7+) for massive data updates.
3. Act (Execution Phase):
   • Write efficient and safe Linq queries.
   • Implement entity configuration classes (IEntityTypeConfiguration).
   • Create and execute database migration commands.
4. Validate (Standard Validation):
   • Check if the generated SQL meets performance expectations (avoiding full table scans).
   • Validate concurrency conflict handling logic.
   • Ensure all database accesses follow asynchronous patterns.

Feature Roadmap (.NET 6 - 10)

.NET 6 & 7 (Foundation)

• Split Queries: Solve the Cartesian product problem.
• Bulk Operations: Use ExecuteUpdate/Delete for high-performance updates.
• JSON Columns: Built-in JSON mapping support.
• Compiled Models: Reduce startup time for large models.

.NET 8 & 9 (Productivity)

• Primitive Collections: Use simple type collections in queries.
• HierarchyId: Support for SQL Server hierarchical data.
• Auto-compiled Queries: Further optimize the query compilation process.
• Complex Types: Better support for Value Objects.

.NET 10+ (Version-Specific Features)

• Advanced Interceptors: More query lifecycle hooks.
• Optimized AOT Support: AOT pre-compilation optimization for cloud-native environments.

Coding Standards

• Fluent API Preference: Prioritize entity configuration classes over Data Annotations.
• Async Always: All I/O operations must be asynchronous.
• No-Tracking by Default: Read-only queries must always use .AsNoTracking().
• Naming: Entity names correspond to tables, foreign key names have clear semantics.

Deliver

• Optimized Linq Queries: Provide query code with the potential for high-performance SQL translation.
• Migration Scripts & Guidance: Provide correct migration commands and manual adjustment suggestions.
• Database Schema Design: Design normalized entity relationships based on business requirements.

Validate

• Ensure the provided code complies with EF Core performance best practices.
• Validate whether the code correctly handles Nulls and database constraints.
• Confirm database connection and resource release logic is correct (using using or Scoped DI).

Documentation

Official References

• Entity Framework Core Overview
• Performance Optimization in EF Core
• Supported Database Providers

Internal References

• EF Core Coding Style and Naming Conventions
• EF Core Anti-Patterns and Best Practices
• EF Core Modern Patterns Guide