Fix to #21607 - Incorrect results returned when joining a key-less vi…

…ew to an entity (#21723)

Disabling the scenario when we try to add collection join to keyless entity parent, since we don't have identifying columns to properly bucket the results.

Fixes #21607

src/EFCore.Relational/Properties/RelationalStrings.resx

@@ -700,6 +700,9 @@
   <data name="SequenceContainsNoElements" xml:space="preserve">
     <value>Sequence contains no elements.</value>
   </data>
+  <data name="ProjectingCollectionOnKeylessEntityNotSupported" xml:space="preserve">
+    <value>Projecting collection correlated with keyless entity is not supported.</value>
+  </data>
   <data name="LogBatchExecutorFailedToRollbackToSavepoint" xml:space="preserve">
     <value>An error occurred while the batch executor was rolling back the transaction to a savepoint, after an exception occured.</value>
     <comment>Debug RelationalEventId.BatchExecutorFailedToRollbackToSavepoint</comment>

src/EFCore.Relational/Query/SqlExpressions/SelectExpression.cs

@@ -1423,6 +1423,11 @@ public Expression ApplyCollectionJoin(
             else
             {
                 var parentIdentifierList = _identifier.Except(_childIdentifiers).ToList();
+                if (parentIdentifierList.Count == 0)
+                {
+                    throw new InvalidOperationException(RelationalStrings.ProjectingCollectionOnKeylessEntityNotSupported);
+                }
+
                 var (parentIdentifier, parentIdentifierValueComparers) = GetIdentifierAccessor(parentIdentifierList);
                 var (outerIdentifier, outerIdentifierValueComparers) = GetIdentifierAccessor(_identifier);
                 var innerClientEval = innerSelectExpression.Projection.Count > 0;

test/EFCore.Cosmos.FunctionalTests/Query/NorthwindKeylessEntitiesQueryCosmosTest.cs

@@ -137,6 +137,14 @@ public override async Task KeylesEntity_groupby(bool async)
             AssertSql(@"");
         }
 
+        [ConditionalTheory(Skip = "Issue #17246")]
+        public override async Task Collection_correlated_with_keyless_entity_in_predicate_works(bool async)
+        {
+            await base.Collection_correlated_with_keyless_entity_in_predicate_works(async);
+
+            AssertSql(@"");
+        }
+
         private void AssertSql(params string[] expected)
             => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 

test/EFCore.Relational.Specification.Tests/Query/NorthwindKeylessEntitiesQueryRelationalTestBase.cs

@@ -1,7 +1,13 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using Microsoft.EntityFrameworkCore.Diagnostics;
+using Microsoft.EntityFrameworkCore.TestModels.Northwind;
 using Microsoft.EntityFrameworkCore.TestUtilities;
+using Xunit;
 
 namespace Microsoft.EntityFrameworkCore.Query
 {
@@ -15,6 +21,23 @@ protected NorthwindKeylessEntitiesQueryRelationalTestBase(TFixture fixture)
 
         protected virtual bool CanExecuteQueryString => false;
 
+        [ConditionalTheory]
+        [MemberData(nameof(IsAsyncData))]
+        public virtual async Task Projecting_collection_correlated_with_keyless_entity_throws(bool async)
+        {
+            var message = (await Assert.ThrowsAsync<InvalidOperationException>(
+                () => AssertQuery(
+                    async,
+                    ss => ss.Set<CustomerQuery>().Select(cq => new
+                    {
+                        cq.City,
+                        cq.CompanyName,
+                        OrderDetailIds = ss.Set<Customer>().Where(c => c.City == cq.City).ToList()
+                    }).OrderBy(x => x.City).Take(2)))).Message;
+
+            Assert.Equal(RelationalStrings.ProjectingCollectionOnKeylessEntityNotSupported, message);
+        }
+
         protected override QueryAsserter CreateQueryAsserter(TFixture fixture)
             => new RelationalQueryAsserter(fixture, RewriteExpectedQueryExpression, RewriteServerQueryExpression, canExecuteQueryString: CanExecuteQueryString);
     }

test/EFCore.Specification.Tests/Query/NorthwindKeylessEntitiesQueryTestBase.cs

@@ -199,5 +199,18 @@ from pv in grouping.DefaultIfEmpty()
 
             Assert.Equal(830, results.Count);
         }
+
+        [ConditionalTheory]
+        [MemberData(nameof(IsAsyncData))]
+        public virtual Task Collection_correlated_with_keyless_entity_in_predicate_works(bool async)
+        {
+            return AssertQuery(
+                async,
+                ss => ss.Set<CustomerQuery>()
+                    .Where(cq => ss.Set<Customer>().Where(c => c.City == cq.City).Any())
+                    .Select(pv => new { pv.City, pv.ContactName })
+                    .OrderBy(x => x.ContactName)
+                    .Take(2));
+        }
     }
 }

test/EFCore.Specification.Tests/Query/NorthwindQueryFixtureBase.cs

@@ -28,6 +28,7 @@ public IReadOnlyDictionary<Type, object> GetEntitySorters()
                 { typeof(OrderQuery), e => ((OrderQuery)e)?.CustomerID },
                 { typeof(Employee), e => ((Employee)e)?.EmployeeID },
                 { typeof(Product), e => ((Product)e)?.ProductID },
+                { typeof(ProductQuery), e => ((ProductQuery)e)?.ProductID },
                 { typeof(OrderDetail), e => (((OrderDetail)e)?.OrderID.ToString(), ((OrderDetail)e)?.ProductID.ToString()) }
             }.ToDictionary(e => e.Key, e => (object)e.Value);
 

test/EFCore.Specification.Tests/TestModels/Northwind/NorthwindData.cs

@@ -16,6 +16,7 @@ public partial class NorthwindData : ISetSource
         private readonly CustomerQuery[] _customerQueries;
         private readonly Employee[] _employees;
         private readonly Product[] _products;
+        private readonly ProductQuery[] _productQueries;
         private readonly Order[] _orders;
         private readonly OrderQuery[] _orderQueries;
         private readonly OrderDetail[] _orderDetails;
@@ -48,11 +49,21 @@ public NorthwindData()
 
             _customerQueries = customerQueries.ToArray();
 
+            var productQueries = new List<ProductQuery>();
+
             foreach (var product in _products)
             {
                 product.OrderDetails = new List<OrderDetail>();
+
+                if (!product.Discontinued)
+                {
+                    productQueries.Add(
+                        new ProductQuery { CategoryName = "Food", ProductID = product.ProductID, ProductName = product.ProductName });
+                }
             }
 
+            _productQueries = productQueries.ToArray();
+
             var orderQueries = new List<OrderQuery>();
 
             foreach (var order in _orders)
@@ -125,6 +136,11 @@ public IQueryable<TEntity> Set<TEntity>()
                 return (IQueryable<TEntity>)_orderQueries.AsQueryable();
             }
 
+            if (typeof(TEntity) == typeof(ProductQuery))
+            {
+                return (IQueryable<TEntity>)_productQueries.AsQueryable();
+            }
+
             throw new InvalidOperationException("Invalid entity type: " + typeof(TEntity));
         }
 

test/EFCore.SqlServer.FunctionalTests/Query/NorthwindKeylessEntitiesQuerySqlServerTest.cs

@@ -168,6 +168,24 @@ FROM [Orders] AS [o]
 LEFT JOIN [Alphabetical list of products] AS [a] ON [o].[CustomerID] = [a].[CategoryName]");
         }
 
+        public override async Task Collection_correlated_with_keyless_entity_in_predicate_works(bool async)
+        {
+            await base.Collection_correlated_with_keyless_entity_in_predicate_works(async);
+
+            AssertSql(
+                @"@__p_0='2'
+
+SELECT TOP(@__p_0) [c].[City], [c].[ContactName]
+FROM (
+    SELECT [c].[CustomerID] + N'' as [CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region] FROM [Customers] AS [c]
+) AS [c]
+WHERE EXISTS (
+    SELECT 1
+    FROM [Customers] AS [c0]
+    WHERE ([c0].[City] = [c].[City]) OR ([c0].[City] IS NULL AND [c].[City] IS NULL))
+ORDER BY [c].[ContactName]");
+        }
+
         private void AssertSql(params string[] expected)
             => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);