1. Learn. Imagine. Build. .NET Conf
What’s new in Entity Framework Core 2.0
Andrew Peters
Diego Vega
Learn. Imagine. Build. .NET Conf

2. Entity Framework versions
Microsoft Build 2017
9/19/2018 6:53 PM
Entity Framework versions
Entity Framework
O/R Mapper for .NET Framework
EF 6.2 (ETA really soon)
EF 6.x
EF 5.x
EF 4.x
EF 3.5
Entity Framework Core
Lightweight, extensible, and cross-platform O/RM for .NET Standard
EF Core 2.0 (latest)
EF Core 1.x
EF Core 2.1 (ETA Q1 2018)
How to think about EF 6 and EF Core
Entity Framework Started more than 10 years ago
Many versions
Started with .NET 3.5 SP1 around the time that LINQ became a thing
Built for .NET Framework  Windows Only (although Mono has a version of it)
Entity Framework Core is quite new
Built for .NET Standard
Cross platform
Version 1.1 and 2.0 out, 2.1. coming out in a few months
EF 6.2 coming out soon
Important:
EF Core is not a replacement for EF or the next version of EF 6
Both trains continue to go forward
EF Core will see more innovation
EF 6 is a Microsoft supported product, will have minor improvements and minor fixes, mostly driven by the community
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3. EF Core 2.0 themes .NET Standard 2.0 Quality Performance
Close feature gap
Reusable building blocks

4. Demo Flexible Object Mapping 9/19/2018 6:53 PM
Fluent API for navigation properties mapped to field
Type conversions
Custom collection mapping
Richer collection support
Custom property access patterns
Collections of scalar types
Factory methods and DI
Setting properties in constructor parameters
Custom object construction patterns
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

5. Demo DbContext Pooling 9/19/2018 6:53 PM
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6. DbContext per Request DI Container
Microsoft Build 2017
9/19/2018 6:53 PM
DbContext per Request
DI Container
public class BlogsController : Controller {
private BlogContext _context;
public BlogsController(BlogContext context)
_context = context; }
public IActionResult Index()
return _context.Blogs.ToList();
Request: /blogs/index
Scope
BlogContext
Controller
Blogs
Scope
Controller
Blogs
BlogContext
Request: /blogs/index
Scope
Controller
Blogs
BlogContext
Request: /blogs/index
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

7. DbContext Pooling DI Container
Microsoft Build 2017
9/19/2018 6:53 PM
DbContext Pooling
DI Container
public class BlogsController : Controller {
private BlogContext _context;
public BlogsController(BlogContext context)
_context = context; }
public IActionResult Index()
return _context.Blogs.ToList();
Request: /blogs/index
Context Pool
Scope
Scope
BlogContext
Controller
Blogs
BlogContext
BlogContext
BlogContext
BlogContext
Scope
Controller
Blogs
Request: /blogs/index
BlogContext
BlogContext
Allow the connection string to be mutated
Mechanism for user state reset
Scope
Controller
Blogs
Request: /blogs/index
BlogContext
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

8. Demo Explicit Compiled Queries 9/19/2018 6:53 PM
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9. Demo Owned Types and Table Splitting 9/19/2018 6:53 PM
Collections of owned types
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

10. Demo Global Query Filters 9/19/2018 6:53 PM
Filter specification with navigation properties
Filters for derived types
Selectively disable filters
Global sort order
Defining queries
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

11. Demo String Interpolation for raw SQL queries 9/19/2018 6:53 PM
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

12. EF Core 2.1 GroupBy translation Lazy loading
9/19/2018 6:53 PM
EF Core 2.1
GroupBy translation
Lazy loading
Mapping types without keys
Data seeding
Type conversions
Lifecyle hooks
Column ordering
Cosmos DB provider
Sample Oracle provider
Include for derived types
Non-default constructors
Update model from database
System.Transactions
Backlog:
Many-to-many
Stored procedures
Table-Per-Type
Entity splitting
Easier logging
Spatial
SQL Server Temporal tables
Better support for views
Table rebuilds in migrations
Visual Studio Wizard for EF Core
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13. Session resources Docs https://docs.microsoft.com/ef/core
9/19/2018 6:53 PM
Session resources
Docs
Project
Blog
Demos
Use this slide to share additional content available that attendees should know about. In this section you can call out whitepapers or websites that you and your team have created.
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14. .NET