1. Introduction to Entity Framework Core
Entity Framework Core (EF Core) is a new object-database mapping framework for .NET. It supports LINQ queries, track changes, updates and structural changes. EF Core works with SQL Server / SQL Azure, SQLite, Azure Cosmos DB, MySQL, PostgreSQL, and many other databases through the database plugin model.
2. Introduction to Entity Framework 6
Entity Framework 6 (EF6) is an object relational mapping framework designed for the .NET Framework but with .NET Core support. EF6 is a stable, supported product, but is no longer actively developed.
3. Compare Entity Framework Core and Entity Framework 6
EF Core offers new features that will not be implemented in EF6. However, not all EF6 features are currently implemented in the EF Core. The following tables compare the features available in EF Core and EF6. This is a high-level comparison and does not list every feature or explain the differences between the same feature in different EF versions.
Create model
| Feature | EF 6.4 | EF Core |
|---|---|---|
| Basic class mapping | Yes | 1.0 |
| Basic class mapping | Yes | 1.0 |
| Constructors with parameters | 2.1 | |
| Property value conversions | 2.1 | |
| Mapped types with no keys | 2.1 | |
| Conventions | Yes | 1.0 |
| Custom conventions | Yes | 1.0 (partial) |
| Data annotations | Yes | 1.0 |
| Fluent API | Yes | 1.0 |
| Inheritance: Table per hierarchy (TPH) | Yes | 1.0 |
| Inheritance: Table per type (TPT) | Yes | Planned for 5.0 |
| Inheritance: Table per concrete class (TPC) | Yes | Stretch for 5.0 (1) |
| Shadow state properties | 1.0 | |
| Alternate keys | 1.0 | |
| Many-to-many navigations | Yes | Planned for 5.0 |
| Many-to-many without join entity | Yes | On the backlog |
| Key generation: Database | Yes | 1.0 |
| Key generation: Client | 1.0 | |
| Complex / owned types | Yes | 2.0 |
| Spatial data | Yes | 2.2 |
| Model format: Code | Yes | 1.0 |
| Create model from database: Command line | Yes | 1.0 |
| Update model from database | Partial | On the backlog |
| Global query filters | 2.0 | |
| Table splitting | Yes | |
| Entity splitting | Yes | Stretch for 5.0 (# 620) (1) |
| Database scalar function mapping | Poor | 2.0 |
| Field mapping | 1.1 | |
| Nullable reference types (C # 8.0) | 3.0 | |
| Graphical visualization of model | Yes | No support planned (2) |
| Graphical model editor | Yes | No support planned (2) |
| Model format: EDMX (XML) | Yes | No support planned (2) |
| Create model from database: VS wizard | Yes | No support planned (2) |
Data access
| Feature | EF 6.4 | EF Core |
|---|---|---|
| LINQ queries | Yes | 1.0 |
| Readable generated SQL | Poor | 1.0 |
| GroupBy translation | Yes | 2.1 |
| Loading related data: Eager | Yes | 1.0 |
| Loading related data: Eager loading for derived types | 2.1 | |
| Loading related data: Lazy | Yes | 2.1 |
| Loading related data: Explicit | Yes | 1.1 |
| Raw SQL queries: Entity types | Yes | 1.0 |
| Raw SQL queries: Keyless entity types | Yes | 2.1 |
| Raw SQL queries: Composing with LINQ | 1.0 | |
| Explicitly compiled queries | Poor | 2.0 |
| await foreach (C # 8.0) | 3.0 | |
| Text-based query language (Entity SQL) | Yes | No support planned (2) |
Save the data
| Feature | EF 6.4 | EF Core |
|---|---|---|
| Change tracking: Snapshot | Yes | 1.0 |
| Change tracking: Notification | Yes | 1.0 |
| Change tracking: Proxies | Yes | Merged for 5.0 |
| Accessing tracked state | Yes | 1.0 |
| Optimistic concurrency | Yes | 1.0 |
| Transactions | Yes | 1.0 |
| Batching of statements | 1.0 | |
| Stored procedure mapping | Yes | On the backlog |
| Disconnected graph low-level APIs | Poor | 1.0 |
| Disconnected graph End-to-end | 1.0 |
Other function
| Feature | EF 6.4 | EF Core |
|---|---|---|
| Migrations | Yes | 1.0 |
| Database creation / deletion APIs | Yes | 1.0 |
| Seed data | Yes | 2.1 |
| Connection resiliency | Yes | 1.1 |
| Interceptors | Yes | 3.0 |
| Events | Yes | 3.0 (partial) |
| Simple Logging (Database.Log) | Yes | Merged for 5.0 |
| DbContext pooling | 2.0 |
Databases are supported
| Feature | EF 6.4 | EF Core |
|---|---|---|
| SQL Server | Yes | 1.0 |
| MySQL | Yes | 1.0 |
| PostgreSQL | Yes | 1.0 |
| Oracle | Yes | 1.0 |
| SQLite | Yes | 1.0 |
| SQL Server Compact | Yes | 1.0 (4) |
| DB2 | Yes | 1.0 |
| Firebird | Yes | 2.0 |
| Jet (Microsoft Access) | 2.0 (4) | |
| Azure Cosmos DB | 3.0 | |
| In-memory (for testing) | 1.0 |
Note:
(1): Not yet likely to appear for a given release. However, it will appear soon in the future.
(2): Some features of EF6 will not be implemented in EF Core.
(3): Third-party-deployed EF Core database may be delayed in updating to new versions of EF Core.
(4): SQL Server Compact and Jet only work on .NET Framework (not on .NET Core).
4. Supporting platform
EF Core 3.1 runs on .NET Core and .NET Framework, through the use of .NET Standard 2.0. However, EF Core 5.0 will not run on the .NET Framework. EF6.4 runs on .NET Core and .NET Framework through multi-targeting.
5. Conclusion
Above are some comparisons between EF Core and EF6. Each framework has advantages and disadvantages. In the future, the EF Core will gradually have all the features of the EF6 but at the present time the EF6 will probably operate more stably. So you can rely on your own comparisons and needs to choose the right framework for your current project and hope your article can partially support you to make a decision.