entity-framework-core

Name: entity-framework-core
Author: managedcode

40installs35forks

How to install entity-framework-core?

managedcode/dotnet-skills/entity-framework-core

$npx -y skills add managedcode/dotnet-skills --skill entity-framework-core

Installs into the current project.

Summary

Design, tune, or review EF Core data access with proper modeling, migrations, query translation, performance, and lifetime management for modern .NET applications. USE FOR: DbContext, migrations, model configuration, EF queries, tracking, loading, performance, transactions, and E

Files · 1

View on GitHub

SKILL.md

1	# Entity Framework Core
2
3	## Trigger On
4
5	- working on `DbContext`, migrations, model configuration, or EF queries
6	- reviewing tracking, loading, performance, or transaction behavior
7	- porting data access from EF6 or custom repositories to EF Core
8	- optimizing slow database queries
9
10	## Documentation
11
12	- [EF Core Overview](https://learn.microsoft.com/en-us/ef/core/)
13	- [Performance](https://learn.microsoft.com/en-us/ef/core/performance/)
14	- [Efficient Querying](https://learn.microsoft.com/en-us/ef/core/performance/efficient-querying)
15	- [Migrations](https://learn.microsoft.com/en-us/ef/core/managing-schemas/migrations/)
16	- [What's New in EF Core 9](https://learn.microsoft.com/en-us/ef/core/what-is-new/ef-core-9.0/whatsnew)
17
18	### References
19
20	- [patterns.md](references/patterns.md) - Query patterns, tracking strategies, loading strategies, projections, compiled queries, pagination, and temporal tables
21	- [anti-patterns.md](references/anti-patterns.md) - Common EF Core mistakes including N+1 queries, large contexts, generic repositories, and missing indexes
22
23	## Workflow
24
25	1. Prefer EF Core for new development unless a documented gap requires Dapper or raw SQL
26	2. Keep `DbContext` lifetime scoped — align with unit of work
27	3. Review query translation — check generated SQL, avoid N+1
28	4. Treat migrations as first-class — reviewable, not throwaway
29	5. Be deliberate about provider behavior — cross-provider but not identical
30	6. Validate with query inspection — not just in-memory mental model
31
32	## Current Upstream Notes
33
34	- EF Core `v10.0.10` is a servicing release. It fixes an AOT build fork-bomb caused by EF file generation during design-time or command-line builds and an `ordinal -1 is invalid` crash when nested JSON complex sub-collections grow. Re-run AOT publishing and provider-backed JSON query/update tests when those paths apply.
35	- The July 2026 EF Core vs EF6 comparison refresh remains the first stop for migration decisions. EF Core is the active cross-platform stack, but EF6-only EDMX/ObjectContext-heavy code should not move without a feature inventory and database-backed equivalence tests.
36
37	## DbContext Patterns
38
39	### Basic Configuration
40	```csharp
41	public class AppDbContext : DbContext
42	{
43	public DbSet<Product> Products => Set<Product>();
44	public DbSet<Order> Orders => Set<Order>();
45
46	protected override void OnModelCreating(ModelBuilder modelBuilder)
47	{
48	modelBuilder.ApplyConfigurationsFromAssembly(typeof(AppDbContext).Assembly);
49	}
50	}
51
52	// Entity Configuration (Fluent API)
53	public class ProductConfiguration : IEntityTypeConfiguration<Product>
54	{
55	public void Configure(EntityTypeBuilder<Product> builder)
56	{
57	builder.HasKey(p => p.Id);
58	builder.Property(p => p.Name).HasMaxLength(200).IsRequired();
59	builder.HasIndex(p => p.Sku).IsUnique();
60	builder.HasMany(p => p.OrderItems).WithOne(oi => oi.Product);
61	}
62	}
63	```
64
65	### Registration with DI
66	```csharp
67	builder.Services.AddDbContext<AppDbContext>(options =>
68	options.UseSqlServer(connectionString)
69	.EnableSensitiveDataLogging() // Dev only
70	.EnableDetailedErrors()); // Dev only
71
72	// Or with pooling (better performance)
73	builder.Services.AddDbContextPool<AppDbContext>(options =>
74	options.UseSqlServer(connectionString));
75	```
76
77	## Query Patterns
78
79	### Use AsNoTracking for Read-Only
80	```csharp
81	// Bad - tracks entities unnecessarily
82	var products = await db.Products.ToListAsync();
83
84	// Good - no tracking overhead
85	var products = await db.Products
86	.AsNoTracking()
87	.ToListAsync();
88	```
89
90	### Project to DTOs
91	```csharp
92	// Bad - loads entire entity graph
93	var orders = await db.Orders
94	.Include(o => o.Items)
95	.Include(o => o.Customer)
96	.ToListAsync();
97
98	// Good - loads only needed data
99	var orders = await db.Orders
100	.Select(o => new OrderDto
101	{
102	Id = o.Id,
103	CustomerName = o.Customer.Name,
104	ItemCount = o.Items.Count,
105	Total = o.Items.Sum(i => i.Price)
106	})
107	.ToListAsync();
108	```
109
110	### Avoid N+1 Queries
111	```csharp
112	// Bad - N+1 problem
113	foreach (var order in orders)
114	{
115	var items = await db.OrderItems
116	.Where(i => i.OrderId == order.Id)
117	.ToListAsync();
118	}
119
120	// Good - eager loading
121	var orders = await db.Orders
122	.Include(o => o.Items)
123	.ToListAsync();
124
125	// Good - split query for large

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entity-framework-core

40installs35forks

View on GitHub

How to install entity-framework-core?

managedcode/dotnet-skills/entity-framework-core

$npx -y skills add managedcode/dotnet-skills --skill entity-framework-core

Installs into the current project.

Summary

Files · 1

View on GitHub

SKILL.md

1	# Entity Framework Core
2
3	## Trigger On
4
5	- working on `DbContext`, migrations, model configuration, or EF queries
6	- reviewing tracking, loading, performance, or transaction behavior
7	- porting data access from EF6 or custom repositories to EF Core
8	- optimizing slow database queries
9
10	## Documentation
11
12	- [EF Core Overview](https://learn.microsoft.com/en-us/ef/core/)
13	- [Performance](https://learn.microsoft.com/en-us/ef/core/performance/)
14	- [Efficient Querying](https://learn.microsoft.com/en-us/ef/core/performance/efficient-querying)
15	- [Migrations](https://learn.microsoft.com/en-us/ef/core/managing-schemas/migrations/)
16	- [What's New in EF Core 9](https://learn.microsoft.com/en-us/ef/core/what-is-new/ef-core-9.0/whatsnew)
17
18	### References
19
20	- [patterns.md](references/patterns.md) - Query patterns, tracking strategies, loading strategies, projections, compiled queries, pagination, and temporal tables
21	- [anti-patterns.md](references/anti-patterns.md) - Common EF Core mistakes including N+1 queries, large contexts, generic repositories, and missing indexes
22
23	## Workflow
24
25	1. Prefer EF Core for new development unless a documented gap requires Dapper or raw SQL
26	2. Keep `DbContext` lifetime scoped — align with unit of work
27	3. Review query translation — check generated SQL, avoid N+1
28	4. Treat migrations as first-class — reviewable, not throwaway
29	5. Be deliberate about provider behavior — cross-provider but not identical
30	6. Validate with query inspection — not just in-memory mental model
31
32	## Current Upstream Notes
33
34	- EF Core `v10.0.10` is a servicing release. It fixes an AOT build fork-bomb caused by EF file generation during design-time or command-line builds and an `ordinal -1 is invalid` crash when nested JSON complex sub-collections grow. Re-run AOT publishing and provider-backed JSON query/update tests when those paths apply.
35	- The July 2026 EF Core vs EF6 comparison refresh remains the first stop for migration decisions. EF Core is the active cross-platform stack, but EF6-only EDMX/ObjectContext-heavy code should not move without a feature inventory and database-backed equivalence tests.
36
37	## DbContext Patterns
38
39	### Basic Configuration
40	```csharp
41	public class AppDbContext : DbContext
42	{
43	public DbSet<Product> Products => Set<Product>();
44	public DbSet<Order> Orders => Set<Order>();
45
46	protected override void OnModelCreating(ModelBuilder modelBuilder)
47	{
48	modelBuilder.ApplyConfigurationsFromAssembly(typeof(AppDbContext).Assembly);
49	}
50	}
51
52	// Entity Configuration (Fluent API)
53	public class ProductConfiguration : IEntityTypeConfiguration<Product>
54	{
55	public void Configure(EntityTypeBuilder<Product> builder)
56	{
57	builder.HasKey(p => p.Id);
58	builder.Property(p => p.Name).HasMaxLength(200).IsRequired();
59	builder.HasIndex(p => p.Sku).IsUnique();
60	builder.HasMany(p => p.OrderItems).WithOne(oi => oi.Product);
61	}
62	}
63	```
64
65	### Registration with DI
66	```csharp
67	builder.Services.AddDbContext<AppDbContext>(options =>
68	options.UseSqlServer(connectionString)
69	.EnableSensitiveDataLogging() // Dev only
70	.EnableDetailedErrors()); // Dev only
71
72	// Or with pooling (better performance)
73	builder.Services.AddDbContextPool<AppDbContext>(options =>
74	options.UseSqlServer(connectionString));
75	```
76
77	## Query Patterns
78
79	### Use AsNoTracking for Read-Only
80	```csharp
81	// Bad - tracks entities unnecessarily
82	var products = await db.Products.ToListAsync();
83
84	// Good - no tracking overhead
85	var products = await db.Products
86	.AsNoTracking()
87	.ToListAsync();
88	```
89
90	### Project to DTOs
91	```csharp
92	// Bad - loads entire entity graph
93	var orders = await db.Orders
94	.Include(o => o.Items)
95	.Include(o => o.Customer)
96	.ToListAsync();
97
98	// Good - loads only needed data
99	var orders = await db.Orders
100	.Select(o => new OrderDto
101	{
102	Id = o.Id,
103	CustomerName = o.Customer.Name,
104	ItemCount = o.Items.Count,
105	Total = o.Items.Sum(i => i.Price)
106	})
107	.ToListAsync();
108	```
109
110	### Avoid N+1 Queries
111	```csharp
112	// Bad - N+1 problem
113	foreach (var order in orders)
114	{
115	var items = await db.OrderItems
116	.Where(i => i.OrderId == order.Id)
117	.ToListAsync();
118	}
119
120	// Good - eager loading
121	var orders = await db.Orders
122	.Include(o => o.Items)
123	.ToListAsync();
124
125	// Good - split query for large

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Type