Drop markdown headings to solve dup headings (#19847)

guardrex · web-flow · commit 14a9317fb062 · 2020-09-14T09:24:21.000-05:00
diff --git a/aspnetcore/blazor/blazor-server-ef-core.md b/aspnetcore/blazor/blazor-server-ef-core.md
@@ -20,7 +20,7 @@ Blazor Server is a stateful app framework. The app maintains an ongoing connecti
 > [!NOTE]
 > This article addresses EF Core in Blazor Server apps. Blazor WebAssembly apps run in a WebAssembly sandbox that prevents most direct database connections. Running EF Core in Blazor WebAssembly is beyond the scope of this article.
 
-## Sample app
+<h2 id="sample-app-5x">Sample app</h2>
 
 The sample app was built as a reference for Blazor Server apps that use EF Core. The sample app includes a grid with sorting and filtering, delete, add, and update operations. The sample demonstrates use of EF Core to handle optimistic concurrency.
 
@@ -35,7 +35,7 @@ The grid, add, and view components use the "context-per-operation" pattern, wher
 > [!NOTE]
 > Some of the code examples in this topic require namespaces and services that aren't shown. To inspect the fully working code, including the required [`@using`](xref:mvc/views/razor#using) and [`@inject`](xref:mvc/views/razor#inject) directives for Razor examples, see the [sample app](https://github.com/dotnet/AspNetCore.Docs/tree/master/aspnetcore/blazor/common/samples/5.x/BlazorServerEFCoreSample).
 
-## Database access
+<h2 id="database-access-5x">Database access</h2>
 
 EF Core relies on a <xref:Microsoft.EntityFrameworkCore.DbContext> as the means to [configure database access](/ef/core/miscellaneous/configuring-dbcontext) and act as a [*unit of work*](https://martinfowler.com/eaaCatalog/unitOfWork.html). EF Core provides the <xref:Microsoft.Extensions.DependencyInjection.EntityFrameworkServiceCollectionExtensions.AddDbContext%2A> extension for ASP.NET Core apps that registers the context as a *scoped* service by default. In Blazor Server apps, scoped service registrations can be problematic because the instance is shared across components within the user's circuit. <xref:Microsoft.EntityFrameworkCore.DbContext> isn't thread safe and isn't designed for concurrent use. The existing lifetimes are inappropriate for these reasons:
 
@@ -75,9 +75,9 @@ The following recommendations are designed to provide a consistent approach to u
 
   Place operations after the `Loading = true;` line in the `try` block.
 
-* For longer-lived operations that take advantage of EF Core's [change tracking](/ef/core/querying/tracking) or [concurrency control](/ef/core/saving/concurrency), [scope the context to the lifetime of the component](#scope-to-the-component-lifetime).
+* For longer-lived operations that take advantage of EF Core's [change tracking](/ef/core/querying/tracking) or [concurrency control](/ef/core/saving/concurrency), [scope the context to the lifetime of the component](#scope-to-the-component-lifetime-5x).
 
-### New DbContext instances
+<h3 id="new-dbcontext-instances-5x">New DbContext instances</h3>
 
 The fastest way to create a new <xref:Microsoft.EntityFrameworkCore.DbContext> instance is by using `new` to create a new instance. However, there are several scenarios that may require resolving additional dependencies. For example, you may wish to use [`DbContextOptions`](/ef/core/miscellaneous/configuring-dbcontext#configuring-dbcontextoptions) to configure the context.
 
@@ -94,7 +94,7 @@ The factory is injected into components and used to create new instances. For ex
 > [!NOTE]
 > `Wrapper` is a [component reference](xref:blazor/components/index#capture-references-to-components) to the `GridWrapper` component. See the `Index` component (`Pages/Index.razor`) in the [sample app](https://github.com/dotnet/AspNetCore.Docs/blob/master/aspnetcore/blazor/common/samples/5.x/BlazorServerEFCoreSample/BlazorServerDbContextExample/Pages/Index.razor).
 
-### Scope to the component lifetime
+<h3 id="scope-to-the-component-lifetime-5x">Scope to the component lifetime</h3>
 
 You may wish to create a <xref:Microsoft.EntityFrameworkCore.DbContext> that exists for the lifetime of a component. This allows you to use it as a [unit of work](https://martinfowler.com/eaaCatalog/unitOfWork.html) and take advantage of built-in features, such as change tracking and concurrency resolution.
 You can use the factory to create a context and track it for the lifetime of the component. First, implement <xref:System.IDisposable> and inject the factory as shown in `Pages/EditContact.razor`:
@@ -121,7 +121,7 @@ Blazor Server is a stateful app framework. The app maintains an ongoing connecti
 > [!NOTE]
 > This article addresses EF Core in Blazor Server apps. Blazor WebAssembly apps run in a WebAssembly sandbox that prevents most direct database connections. Running EF Core in Blazor WebAssembly is beyond the scope of this article.
 
-## Sample app
+<h2 id="sample-app-3x">Sample app</h2>
 
 The sample app was built as a reference for Blazor Server apps that use EF Core. The sample app includes a grid with sorting and filtering, delete, add, and update operations. The sample demonstrates use of EF Core to handle optimistic concurrency.
 
@@ -136,16 +136,14 @@ The grid, add, and view components use the "context-per-operation" pattern, wher
 > [!NOTE]
 > Some of the code examples in this topic require namespaces and services that aren't shown. To inspect the fully working code, including the required [`@using`](xref:mvc/views/razor#using) and [`@inject`](xref:mvc/views/razor#inject) directives for Razor examples, see the [sample app](https://github.com/dotnet/AspNetCore.Docs/tree/master/aspnetcore/blazor/common/samples/3.x/BlazorServerEFCoreSample).
 
-## Database access
+<h2 id="database-access-3x">Database access</h2>
 
 EF Core relies on a <xref:Microsoft.EntityFrameworkCore.DbContext> as the means to [configure database access](/ef/core/miscellaneous/configuring-dbcontext) and act as a [*unit of work*](https://martinfowler.com/eaaCatalog/unitOfWork.html). EF Core provides the <xref:Microsoft.Extensions.DependencyInjection.EntityFrameworkServiceCollectionExtensions.AddDbContext%2A> extension for ASP.NET Core apps that registers the context as a *scoped* service by default. In Blazor Server apps, this can be problematic because the instance is shared across components within the user's circuit. <xref:Microsoft.EntityFrameworkCore.DbContext> isn't thread safe and isn't designed for concurrent use. The existing lifetimes are inappropriate for these reasons:
 
 * **Singleton** shares state across all users of the app and leads to inappropriate concurrent use.
 * **Scoped** (the default) poses a similar issue between components for the same user.
 * **Transient** results in a new instance per request; but as components can be long-lived, this results in a longer-lived context than may be intended.
 
-## Database access
-
 The following recommendations are designed to provide a consistent approach to using EF Core in Blazor Server apps.
 
 * By default, consider using one context per operation. The context is designed for fast, low overhead instantiation:
@@ -178,9 +176,9 @@ The following recommendations are designed to provide a consistent approach to u
 
   Place operations after the `Loading = true;` line in the `try` block.
 
-* For longer-lived operations that take advantage of EF Core's [change tracking](/ef/core/querying/tracking) or [concurrency control](/ef/core/saving/concurrency), [scope the context to the lifetime of the component](#scope-to-the-component-lifetime).
+* For longer-lived operations that take advantage of EF Core's [change tracking](/ef/core/querying/tracking) or [concurrency control](/ef/core/saving/concurrency), [scope the context to the lifetime of the component](#scope-to-the-component-lifetime-3x).
 
-### Create new DbContext instances
+<h3 id="new-dbcontext-instances-3x">New DbContext instances</h3>
 
 The fastest way to create a new <xref:Microsoft.EntityFrameworkCore.DbContext> instance is by using `new` to create a new instance. However, there are several scenarios that may require resolving additional dependencies. For example, you may wish to use [`DbContextOptions`](/ef/core/miscellaneous/configuring-dbcontext#configuring-dbcontextoptions) to configure the context.
 
@@ -201,7 +199,7 @@ The factory is injected into components and used to create new instances. For ex
 > [!NOTE]
 > `Wrapper` is a [component reference](xref:blazor/components/index#capture-references-to-components) to the `GridWrapper` component. See the `Index` component (`Pages/Index.razor`) in the [sample app](https://github.com/dotnet/AspNetCore.Docs/blob/master/aspnetcore/blazor/common/samples/3.x/BlazorServerEFCoreSample/BlazorServerDbContextExample/Pages/Index.razor).
 
-### Scope to the component lifetime
+<h3 id="scope-to-the-component-lifetime-3x">Scope to the component lifetime</h3>
 
 You may wish to create a <xref:Microsoft.EntityFrameworkCore.DbContext> that exists for the lifetime of a component. This allows you to use it as a [unit of work](https://martinfowler.com/eaaCatalog/unitOfWork.html) and take advantage of built-in features, such as change tracking and concurrency resolution.
 You can use the factory to create a context and track it for the lifetime of the component. First, implement <xref:System.IDisposable> and inject the factory as shown in `Pages/EditContact.razor`:
