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18 changes: 9 additions & 9 deletions entity-framework/core/modeling/data-seeding.md
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Expand Up @@ -21,25 +21,25 @@ There are several ways this can be accomplished in EF Core:

## Configuration options `UseSeeding` and `UseAsyncSeeding` methods

EF 9 introduced `UseSeeding` and `UseAsyncSeeding` methods, which provide a convenient way of seeding the database with initial data. These methods aim to improve the experience of using custom initialization logic (explained below). They provide one clear location where all the data seeding code can be placed. Moreover, the code inside `UseSeeding` and `UseAsyncSeeding` methods is protected by the [migration locking mechanism](/ef/core/what-is-new/ef-core-9.0/whatsnew#concurrent-migrations) to prevent concurrency issues.
EF 9 introduced <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> methods, which provide a convenient way of seeding the database with initial data. These methods aim to improve the experience of using custom initialization logic (explained below). They provide one clear location where all the data seeding code can be placed. Moreover, the code inside <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> methods is protected by the [migration locking mechanism](/ef/core/what-is-new/ef-core-9.0/whatsnew#concurrent-migrations) to prevent concurrency issues.

The new seeding methods are called as part of [`EnsureCreated`](xref:Microsoft.EntityFrameworkCore.Storage.IDatabaseCreator.EnsureCreated) operation, [`Migrate`](/dotnet/api/microsoft.entityframeworkcore.relationaldatabasefacadeextensions.migrate) and `dotnet ef database update` command, even if there are no model changes and no migrations were applied.
The new seeding methods are called as part of <xref:Microsoft.EntityFrameworkCore.Storage.IDatabaseCreator.EnsureCreated*> operation, <xref:Microsoft.EntityFrameworkCore.RelationalDatabaseFacadeExtensions.Migrate*> and `dotnet ef database update` command, even if there are no model changes and no migrations were applied.

> [!TIP]
> Using `UseSeeding` and `UseAsyncSeeding` is the recommended way of seeding the database with initial data when working with EF Core.
> Using <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> is the recommended way of seeding the database with initial data when working with EF Core.

These methods can be set up in the [options configuration step](/ef/core/dbcontext-configuration/#dbcontextoptions). Here is an example:

[!code-csharp[ContextOptionSeeding](../../../samples/core/Modeling/DataSeeding/DataSeedingContext.cs?name=ContextOptionSeeding)]

> [!NOTE]
> `UseSeeding` is called from the `EnsureCreated` method, and `UseAsyncSeeding` is called from the `EnsureCreatedAsync` method. When using this feature, it is recommended to implement both `UseSeeding` and `UseAsyncSeeding` methods using similar logic, even if the code using EF is asynchronous. EF Core tooling currently relies on the synchronous version of the method and will not seed the database correctly if the `UseSeeding` method is not implemented.
> <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> is called from the <xref:Microsoft.EntityFrameworkCore.Storage.IDatabaseCreator.EnsureCreated*> method, and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> is called from the <xref:Microsoft.EntityFrameworkCore.Storage.IDatabaseCreator.EnsureCreatedAsync*> method. When using this feature, it is recommended to implement both <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> methods using similar logic, even if the code using EF is asynchronous. EF Core tooling currently relies on the synchronous version of the method and will not seed the database correctly if the <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> method is not implemented.

<a name="custom-initialization-logic"></a>

## Custom initialization logic

A straightforward and powerful way to perform data seeding is to use [`DbContext.SaveChangesAsync()`](xref:core/saving/index) before the main application logic begins execution. It is recommended to use `UseSeeding` and `UseAsyncSeeding` for that purpose, however sometimes using these methods is not a good solution. An example scenario is when seeding requires using two different contexts in one transaction. Below is a code sample performing custom initialization in the application directly:
A straightforward and powerful way to perform data seeding is to use <xref:Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync*> before the main application logic begins execution. It is recommended to use <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> for that purpose, however sometimes using these methods is not a good solution. An example scenario is when seeding requires using two different contexts in one transaction. Below is a code sample performing custom initialization in the application directly:

[!code-csharp[Main](../../../samples/core/Modeling/DataSeeding/Program.cs?name=CustomSeeding)]

Expand Down Expand Up @@ -85,10 +85,10 @@ Once the data has been added to the model, [migrations](xref:core/managing-schem
> [!TIP]
> If you need to apply migrations as part of an automated deployment you can [create a SQL script](xref:core/managing-schemas/migrations/applying#sql-scripts) that can be previewed before execution.

Alternatively, you can use `context.Database.EnsureCreatedAsync()` to create a new database containing the managed data, for example for a test database or when using the in-memory provider or any non-relational database. Note that if the database already exists, `EnsureCreatedAsync()` will neither update the schema nor managed data in the database. For relational databases you shouldn't call `EnsureCreatedAsync()` if you plan to use Migrations.
Alternatively, you can use <xref:Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.EnsureCreatedAsync*> to create a new database containing the managed data, for example for a test database or when using the in-memory provider or any non-relational database. Note that if the database already exists, <xref:Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.EnsureCreatedAsync*> will neither update the schema nor managed data in the database. For relational databases you shouldn't call <xref:Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.EnsureCreatedAsync*> if you plan to use Migrations.

> [!NOTE]
> Populating the database using the `HasData` method used to be referred to as "data seeding". This naming sets incorrect expectations, as the feature has a number of limitations and is only appropriate for specific types of data. That is why we decided to rename it to "model managed data". `UseSeeding` and `UseAsyncSeeding` methods should be used for general purpose data seeding.
> Populating the database using the <xref:Microsoft.EntityFrameworkCore.Metadata.Builders.EntityTypeBuilder`1.HasData*> method used to be referred to as "data seeding". This naming sets incorrect expectations, as the feature has a number of limitations and is only appropriate for specific types of data. That is why we decided to rename it to "model managed data". <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> methods should be used for general purpose data seeding.

### Limitations of model managed data

Expand All @@ -99,7 +99,7 @@ This type of data is managed by migrations and the script to update the data tha

Therefore this feature is most useful for static data that's not expected to change outside of migrations and does not depend on anything else in the database, for example ZIP codes.

If your scenario includes any of the following it is recommended to use `UseSeeding` and `UseAsyncSeeding` methods described in the first section:
If your scenario includes any of the following it is recommended to use <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseSeeding*> and <xref:Microsoft.EntityFrameworkCore.DbContextOptionsBuilder.UseAsyncSeeding*> methods described in the first section:

* Temporary data for testing
* Data that depends on database state
Expand All @@ -113,6 +113,6 @@ If your scenario includes any of the following it is recommended to use `UseSeed

## Manual migration customization

When a migration is added the changes to the data specified with `HasData` are transformed to calls to `InsertData()`, `UpdateData()`, and `DeleteData()`. One way of working around some of the limitations of `HasData` is to manually add these calls or [custom operations](xref:core/managing-schemas/migrations/operations) to the migration instead.
When a migration is added the changes to the data specified with <xref:Microsoft.EntityFrameworkCore.Metadata.Builders.EntityTypeBuilder`1.HasData*> are transformed to calls to `InsertData()`, `UpdateData()`, and `DeleteData()`. One way of working around some of the limitations of <xref:Microsoft.EntityFrameworkCore.Metadata.Builders.EntityTypeBuilder`1.HasData*> is to manually add these calls or [custom operations](xref:core/managing-schemas/migrations/operations) to the migration instead.

[!code-csharp[CustomInsert](../../../samples/core/Modeling/DataSeeding/Migrations/20241016041555_Initial.cs?name=CustomInsert)]
30 changes: 15 additions & 15 deletions entity-framework/core/providers/cosmos/querying.md
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Expand Up @@ -144,7 +144,7 @@ foreach (var session in firstPage.Values)
}
```

Rather than terminating the LINQ query with `ToListAsync` or similar, we use the `ToPageAsync` method, instructing it to get at most 10 items in every page (note that there may be fewer items in the database). Since this is our first query, we'd like to get results from the beginning, and pass `null` as the continuation token. `ToPageAsync` returns a `CosmosPage`, which exposes a continuation token and the values in the page (up to 10 items). Your program will typically send those values to the client, along with the continuation token; this will allow resuming the query later and fetching more results.
Rather than terminating the LINQ query with `ToListAsync` or similar, we use the <xref:Microsoft.EntityFrameworkCore.CosmosQueryableExtensions.ToPageAsync*> method, instructing it to get at most 10 items in every page (note that there may be fewer items in the database). Since this is our first query, we'd like to get results from the beginning, and pass `null` as the continuation token. <xref:Microsoft.EntityFrameworkCore.CosmosQueryableExtensions.ToPageAsync*> returns a <xref:Microsoft.EntityFrameworkCore.CosmosPage`1>, which exposes a continuation token and the values in the page (up to 10 items). Your program will typically send those values to the client, along with the continuation token; this will allow resuming the query later and fetching more results.

Let's assume the user now clicks on the "Next" button in their UI, asking for the next 10 items. You can then execute the query as follows:

Expand All @@ -164,7 +164,7 @@ To learn more about pagination in Azure Cosmos DB, [see this page](/azure/cosmos
> [!NOTE]
> Azure Cosmos DB does not support backwards pagination, and does not provide a count of the total pages or items.
>
> `ToPageAsync` is currently annotated as experimental, since it may be replaced with a more generic EF pagination API that isn't Azure Cosmos DB specific. Although using the current API will generate a compilation warning (`EF9102`), doing so should be safe - future changes may require minor tweaks in the API shape.
> <xref:Microsoft.EntityFrameworkCore.CosmosQueryableExtensions.ToPageAsync*> is currently annotated as experimental, since it may be replaced with a more generic EF pagination API that isn't Azure Cosmos DB specific. Although using the current API will generate a compilation warning (`EF9102`), doing so should be safe - future changes may require minor tweaks in the API shape.

## `FindAsync`

Expand Down Expand Up @@ -209,7 +209,7 @@ FROM (
) s
```

Note that `FromSql` was introduced in EF 9.0. In previous versions, `FromSqlRaw` can be used instead, although note that that method is vulnerable to SQL injection attacks.
Note that <xref:Microsoft.EntityFrameworkCore.CosmosQueryableExtensions.FromSql*> was introduced in EF 9.0. In previous versions, <xref:Microsoft.EntityFrameworkCore.CosmosQueryableExtensions.FromSqlRaw*> can be used instead, although note that that method is vulnerable to SQL injection attacks.

For more information on SQL querying, see the [relational documentation on SQL queries](xref:core/querying/sql-queries); most of that content is relevant for the Azure Cosmos DB provider as well.

Expand Down Expand Up @@ -300,15 +300,15 @@ stringValue.TrimStart() | [LTRIM(@stri

.NET | SQL | Added in
--------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------- | -----
EF.Functions.VectorDistance(vector1, vector2). | [VectorDistance(vector1, vector2)](/azure/cosmos-db/nosql/query/vectordistance) | EF 9
EF.Functions.VectorDistance(vector1, vector2, bruteForce) | [VectorDistance(vector1, vector2, bruteForce)](/azure/cosmos-db/nosql/query/vectordistance) | EF 9
EF.Functions.VectorDistance(vector1, vector2, bruteForce, distanceFunction) | [VectorDistance(vector1, vector2, bruteForce, distanceFunction)](/azure/cosmos-db/nosql/query/vectordistance) | EF 9
EF.Functions.FullTextContains(property, keyword) | [FullTextContains(property, keyword)](/azure/cosmos-db/nosql/query/fulltextcontains) | EF 10
EF.Functions.FullTextContainsAll(property, keyword1, keyword2) | [FullTextContainsAll(property, keyword1, keyword2)](/azure/cosmos-db/nosql/query/fulltextcontainsall) | EF 10
EF.Functions.FullTextContainsAny(property, keyword1, keyword2) | [FullTextContainsAny(property, keyword1, keyword2)](/azure/cosmos-db/nosql/query/fulltextcontainsany) | EF 10
EF.Functions.FullTextScore(property, keyword1, keyword2) | [FullTextScore(property, keyword1, keyword2)](/azure/cosmos-db/nosql/query/fulltextscore) | EF 10
EF.Functions.Rrf(search1, search2) | [RRF(property, search1, search2)](/azure/cosmos-db/nosql/query/rrf). | EF 10
EF.Functions.Rrf(new[] { search1, search2 }, weights) | [RRF(property, search1, search2, weights)](/azure/cosmos-db/nosql/query/rrf) | EF 10
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.VectorDistance*>(vector1, vector2). | [VectorDistance(vector1, vector2)](/azure/cosmos-db/nosql/query/vectordistance) | EF 9
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.VectorDistance*>(vector1, vector2, bruteForce) | [VectorDistance(vector1, vector2, bruteForce)](/azure/cosmos-db/nosql/query/vectordistance) | EF 9
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.VectorDistance*>(vector1, vector2, bruteForce, distanceFunction) | [VectorDistance(vector1, vector2, bruteForce, distanceFunction)](/azure/cosmos-db/nosql/query/vectordistance) | EF 9
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.FullTextContains*>(property, keyword) | [FullTextContains(property, keyword)](/azure/cosmos-db/nosql/query/fulltextcontains) | EF 10
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.FullTextContainsAll*>(property, keyword1, keyword2) | [FullTextContainsAll(property, keyword1, keyword2)](/azure/cosmos-db/nosql/query/fulltextcontainsall) | EF 10
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.FullTextContainsAny*>(property, keyword1, keyword2) | [FullTextContainsAny(property, keyword1, keyword2)](/azure/cosmos-db/nosql/query/fulltextcontainsany) | EF 10
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.FullTextScore*>(property, keyword1, keyword2) | [FullTextScore(property, keyword1, keyword2)](/azure/cosmos-db/nosql/query/fulltextscore) | EF 10
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.Rrf*>(search1, search2) | [RRF(property, search1, search2)](/azure/cosmos-db/nosql/query/rrf). | EF 10
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.Rrf*>(new[] { search1, search2 }, weights) | [RRF(property, search1, search2, weights)](/azure/cosmos-db/nosql/query/rrf) | EF 10

For more information on vector search, see [the documentation](xref:core/providers/cosmos/vector-search). For more information on full-text search, see [the documentation](xref:core/providers/cosmos/full-text-search).

Expand All @@ -317,7 +317,7 @@ For more information on vector search, see [the documentation](xref:core/provide
.NET | SQL | Added in
--------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------- | -----
collection.Contains(item) | @item IN @collection
EF.Functions.CoalesceUndefined(x, y)<sup>1</sup> | [x ?? y](/azure/cosmos-db/nosql/query/ternary-coalesce-operators#coalesce-operator) | EF 9
EF.Functions.IsDefined(x) | [IS_DEFINED(x)](/azure/cosmos-db/nosql/query/is-defined) | EF 9
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.CoalesceUndefined*>(x, y)<sup>1</sup> | [x ?? y](/azure/cosmos-db/nosql/query/ternary-coalesce-operators#coalesce-operator) | EF 9
<xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.IsDefined*>(x) | [IS_DEFINED(x)](/azure/cosmos-db/nosql/query/is-defined) | EF 9

<sup>1</sup> Note that `EF.Functions.CoalesceUndefined` coalesces `undefined`, not `null`. To coalesce `null`, use the regular C# `??` operator.
<sup>1</sup> Note that <xref:Microsoft.EntityFrameworkCore.CosmosDbFunctionsExtensions.CoalesceUndefined*> coalesces `undefined`, not `null`. To coalesce `null`, use the regular C# `??` operator.
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