Add Named Default Constraints to What's New

Author: AndriySvyryd

entity-framework/core/what-is-new/ef-core-10.0/whatsnew.md

@@ -185,6 +185,39 @@ await context.Blogs.ExecuteUpdateAsync(s =>
 
 Thanks to [@aradalvand](https://github.com/aradalvand) for proposing and pushing for this change (in [#32018](https://github.com/dotnet/efcore/issues/32018)).
 
+<a name="default-constrain-names"></a>
+
+## Custom Default Constraint Names
+
+In previous versions of EF Core, when you specified a default value for a property, EF Core would always let the database automatically generate a constraint name. Now, you can explicitly specify the name for default value constraints for SQL Server, giving you more control over your database schema.
+
+You can now specify a constraint name when defining default values in your model configuration:
+
+```C#
+protected override void OnModelCreating(ModelBuilder modelBuilder)
+{
+    modelBuilder.Entity<Blog>()
+        .Property(b => b.IsActive)
+        .HasDefaultValue(true, "DF_Blog_IsActive");
+
+    modelBuilder.Entity<Post>()
+        .Property(p => b.CreatedDate)
+        .HasDefaultValueSql("GETDATE()", "DF_Post_CreatedDate");
+}
+
+```
+
+You can also call `UseNamedDefaultConstraints` to enable automatic naming of all the default constraints. Note that if you have existing migrations then the next migration you add will rename every single default constraint in your model.
+
+```C#
+protected override void OnModelCreating(ModelBuilder modelBuilder)
+{
+    modelBuilder
+        .UseNamedDefaultConstraints();
+}
+
+```
+
 <a name="other-improvements"></a>
 
 ## Other improvements