Document: vector properties not loaded by default in EF Core 11

entity-framework/core/providers/sql-server/vector-search.md

@@ -66,6 +66,9 @@ await context.SaveChangesAsync();
 
 Once you have embeddings saved to your database, you're ready to perform vector similarity search over them.
 
+> [!NOTE]
+> Starting with EF Core 11, vector properties are not loaded by default when querying entities, since vectors are typically large and are rarely needed to be read back. Prior to EF Core 11, vector properties were always loaded like any other property.
+
 ## Exact search with VECTOR_DISTANCE()
 
 The [`EF.Functions.VectorDistance()`](/sql/t-sql/functions/vector-distance-transact-sql) function computes the *exact* distance between two vectors. Use it to perform similarity search for a given user query:
@@ -138,7 +141,7 @@ foreach (var (article, score) in blogs)
 This translates to the following SQL:
 
 ```sql
-SELECT [v].[Id], [v].[Embedding], [v].[Name]
+SELECT [v].[Id], [v].[Name]
 FROM VECTOR_SEARCH([Blogs], 'Embedding', @__embedding, 'metric = cosine', @__topN)
 ```
 
@@ -205,7 +208,7 @@ This query:
 The query produces the following SQL:
 
 ```sql
-SELECT TOP(@p3) [a0].[Id], [a0].[Content], [a0].[Embedding], [a0].[Title]
+SELECT TOP(@p3) [a0].[Id], [a0].[Content], [a0].[Title]
 FROM FREETEXTTABLE([Articles], *, @p, @p1) AS [f]
 LEFT JOIN VECTOR_SEARCH(
     TABLE = [Articles] AS [a0],

entity-framework/core/what-is-new/ef-core-11.0/whatsnew.md

@@ -312,6 +312,25 @@ This translates to the SQL Server [`VECTOR_SEARCH()`](/sql/t-sql/functions/vecto
 
 For more information, see the [full documentation on vector search](xref:core/providers/sql-server/vector-search).
 
+<a name="sqlserver-vector-not-auto-loaded"></a>
+
+### Vector properties not loaded by default
+
+EF Core 11 changes how vector properties are loaded: `SqlVector<T>` columns are no longer included in `SELECT` statements when materializing entities. Since vectors can be quite large—containing hundreds or thousands of floating-point numbers—this avoids unnecessary data transfer in the common case where vectors are ingested and used for search but not read back.
+
+```csharp
+// Vector column is excluded from the projected entity
+var blogs = await context.Blogs.OrderBy(b => b.Name).ToListAsync();
+// Generates: SELECT [b].[Id], [b].[Name] FROM [Blogs] AS [b]
+
+// Explicit projection still loads the vector
+var embeddings = await context.Blogs
+    .Select(b => new { b.Id, b.Embedding })
+    .ToListAsync();
+```
+
+Vector properties can still be used in `WHERE` and `ORDER BY` clauses—including with `VectorDistance()` and `VectorSearch()`—and EF will correctly include them in the SQL, just not in the entity projection.
+
 <a name="sqlserver-full-text-tvf"></a>
 
 ### Full-text search table-valued functions