Fix RowVersion concurrency issue when replacing entities with TPH inheritance and owned types

src/EFCore.Relational/Update/Internal/SharedTableEntryMap.cs

@@ -80,6 +80,21 @@ private IUpdateEntry GetMainEntry(IUpdateEntry entry)
             {
                 return GetMainEntry(principalEntry);
             }
+
+            // When TPH entity replacement causes FindPrincipal to return null (the replacing entry
+            // is an incompatible sibling type), check if the replacing entry's SharedIdentityEntry
+            // is a compatible principal, and use the replacing entry as the main entry.
+            if (principalEntry == null)
+            {
+                var keyValues = foreignKey.Properties.Select(p => entry.GetCurrentValue(p)).ToArray();
+
+                var identityEntry = _updateAdapter.TryGetEntry(foreignKey.PrincipalKey, keyValues);
+                if (identityEntry?.SharedIdentityEntry != null
+                    && foreignKey.PrincipalEntityType.IsAssignableFrom(identityEntry.SharedIdentityEntry.EntityType))
+                {
+                    return GetMainEntry(identityEntry);
+                }
+            }
         }
 
         return entry;

test/EFCore.Relational.Tests/Update/CommandBatchPreparerTest.cs

@@ -1206,6 +1206,121 @@ public void BatchCommands_handles_null_values_when_sensitive_logging_enabled()
         Assert.DoesNotContain("Object reference not set", exception.Message);
     }
 
+    [ConditionalFact]
+    public void BatchCommands_creates_valid_batch_for_replaced_entity_with_TPH_and_owned_type_and_concurrency_token()
+    {
+        var modelBuilder = FakeRelationalTestHelpers.Instance.CreateConventionBuilder();
+
+        modelBuilder.Entity<EntityBase37169>(b =>
+        {
+            b.HasDiscriminator<string>("Type")
+                .HasValue<EntityA37169>(nameof(EntityA37169))
+                .HasValue<EntityB37169>(nameof(EntityB37169));
+
+            b.HasKey(x => x.Id);
+            b.Property(x => x.Id).HasMaxLength(10);
+
+            b.Property(x => x.RowVersion)
+                .IsRequired()
+                .IsRowVersion()
+                .IsConcurrencyToken()
+                .HasConversion<byte[]>();
+        });
+
+        modelBuilder.Entity<EntityA37169>(b =>
+        {
+            b.Property(x => x.SomeValue);
+            b.OwnsOne(x => x.Owned, x =>
+            {
+                x.Property(p => p.CreationDate);
+            });
+        });
+
+        modelBuilder.Entity<EntityB37169>(b =>
+        {
+            b.Property(x => x.Name).HasMaxLength(100);
+        });
+
+        var model = modelBuilder.Model.FinalizeModel();
+        var currentDbContext = CreateContextServices(model).GetRequiredService<ICurrentDbContext>();
+        var stateManager = currentDbContext.GetDependencies().StateManager;
+
+        // Create "existing" EntityA with an owned entity
+        var entityA = new EntityA37169 { Id = "SOMEID", SomeValue = true, Owned = new OwnedEntity37169 { CreationDate = DateTime.UtcNow } };
+        var entityAEntry = stateManager.GetOrCreateEntry(entityA);
+        entityAEntry.SetEntityState(EntityState.Unchanged);
+
+        // Track the owned entity
+        var ownedEntityType = model.FindEntityType(typeof(OwnedEntity37169), "Owned", model.FindEntityType(typeof(EntityA37169)));
+        var ownedEntry = stateManager.GetOrCreateEntry(entityA.Owned, ownedEntityType);
+        ownedEntry.SetEntityState(EntityState.Unchanged);
+
+        // Delete EntityA (owned will cascade)
+        entityAEntry.SetEntityState(EntityState.Deleted);
+        ownedEntry.SetEntityState(EntityState.Deleted);
+
+        // Add EntityB with the same PK
+        var entityB = new EntityB37169 { Id = "SOMEID", Name = "Any" };
+        var entityBEntry = stateManager.GetOrCreateEntry(entityB);
+        entityBEntry.SetEntityState(EntityState.Added);
+
+        // Verify SharedIdentityEntry is set bidirectionally
+        Assert.NotNull(entityBEntry.SharedIdentityEntry);
+        Assert.Same(entityAEntry, entityBEntry.SharedIdentityEntry);
+        Assert.NotNull(entityAEntry.SharedIdentityEntry);
+        Assert.Same(entityBEntry, entityAEntry.SharedIdentityEntry);
+
+        var modelData = new UpdateAdapter(stateManager);
+
+        var commandBatches = CreateBatches(
+            stateManager.GetEntriesToSave(cascadeChanges: true).ToArray(), modelData);
+
+        // Should create valid batch(es) without errors
+        Assert.NotEmpty(commandBatches);
+
+        // Find the command for the replaced entity
+        var allCommands = commandBatches.SelectMany(b => b.ModificationCommands).ToList();
+
+        // The owned entity entry should be part of the same Modified command, not a separate Deleted command
+        var deletedCommands = allCommands.Where(c => c.EntityState == EntityState.Deleted).ToList();
+        Assert.Empty(deletedCommands);
+
+        var modifiedCommand = Assert.Single(allCommands, c => c.EntityState == EntityState.Modified);
+
+        // The modified command should contain both EntityB and OwnedEntity entries
+        Assert.True(modifiedCommand.Entries.Count() >= 2,
+            $"Expected at least 2 entries in Modified command, but got {modifiedCommand.Entries.Count()}. " +
+            $"Total commands: {allCommands.Count}, states: [{string.Join(", ", allCommands.Select(c => c.EntityState))}]");
+
+        // RowVersion should be a condition (used in WHERE clause)
+        var rvModification = modifiedCommand.ColumnModifications
+            .FirstOrDefault(cm => cm.ColumnName == "RowVersion");
+        Assert.NotNull(rvModification);
+        Assert.True(rvModification.IsCondition);
+    }
+
+    private abstract class EntityBase37169
+    {
+        public string Id { get; set; }
+        public long RowVersion { get; set; }
+    }
+
+    private class OwnedEntity37169
+    {
+        public DateTime CreationDate { get; set; }
+    }
+
+    private class EntityA37169 : EntityBase37169
+    {
+        public bool SomeValue { get; set; }
+        public OwnedEntity37169 Owned { get; set; }
+    }
+
+    private class EntityB37169 : EntityBase37169
+    {
+        public string Name { get; set; }
+    }
+
     private class AnotherFakeEntity
     {
         public int Id { get; set; }