Fix to #8492 - Query: incorrect sql generated for query with owned en…

…tities, left join and predicate using inner qsre

Problem was that for queries with owned types that were using GroupJoin-SelectMany-DefaultIfEmpty pattern we were not able to find the owned entity type behind the groupjoin subquery qsre.
Usually (i.e. in case of navigations) we look for the entity type in the lookup on QueryCompilationContext, but if the groupjoin is created manually then this lookup was not populated with entry for the groupjoin subquery.

Fix is to populate the lookup with entry for groupjoin subquery qsre. We do it in nav rewrite, which also populates other entries for owned types.

src/EFCore/Query/ExpressionVisitors/Internal/NavigationRewritingExpressionVisitor.cs

@@ -1368,6 +1368,7 @@ private class NavigationRewritingQueryModelVisitor : ExpressionTransformingQuery
         {
             private readonly CollectionNavigationSubqueryInjector _subqueryInjector;
             private readonly bool _navigationExpansionSubquery;
+            private readonly EntityQueryModelVisitor _queryModelVisitor;
 
             public AdditionalFromClause AdditionalFromClauseBeingProcessed { get; private set; }
 
@@ -1379,10 +1380,19 @@ public NavigationRewritingQueryModelVisitor(
             {
                 _subqueryInjector = new CollectionNavigationSubqueryInjector(queryModelVisitor, shouldInject: true);
                 _navigationExpansionSubquery = navigationExpansionSubquery;
+                _queryModelVisitor = queryModelVisitor;
             }
 
             public override void VisitAdditionalFromClause(AdditionalFromClause fromClause, QueryModel queryModel, int index)
             {
+                // ReSharper disable once PatternAlwaysOfType
+                if (fromClause.TryGetFlattenedGroupJoinClause()?.JoinClause is JoinClause joinClause
+                    // ReSharper disable once PatternAlwaysOfType
+                    && _queryModelVisitor.QueryCompilationContext.FindEntityType(joinClause) is IEntityType entityType)
+                {
+                    _queryModelVisitor.QueryCompilationContext.AddOrUpdateMapping(fromClause, entityType);
+                }
+
                 var oldAdditionalFromClause = AdditionalFromClauseBeingProcessed;
                 AdditionalFromClauseBeingProcessed = fromClause;
                 fromClause.TransformExpressions(TransformingVisitor.Visit);

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

@@ -81,10 +81,41 @@ public override void Nested_group_join_with_take()
             base.Nested_group_join_with_take();
         }
 
-        [ConditionalFact(Skip = "issue #8492")]
+        [ConditionalFact]
         public override void Explicit_GroupJoin_in_subquery_with_unrelated_projection2()
         {
             base.Explicit_GroupJoin_in_subquery_with_unrelated_projection2();
+
+            AssertSql(
+                @"SELECT [t1].[Id]
+FROM (
+    SELECT DISTINCT [l1].*
+    FROM [Level1] AS [l1]
+    LEFT JOIN (
+        SELECT [t].*
+        FROM [Level1] AS [t]
+        WHERE [t].[Id] IS NOT NULL
+    ) AS [t0] ON [l1].[Id] = [t0].[OneToOne_Required_PK_Level1_Optional_Id]
+    WHERE ([t0].[OneToOne_Required_PK_Name] <> N'Foo') OR [t0].[OneToOne_Required_PK_Name] IS NULL
+) AS [t1]");
+        }
+
+        [ConditionalFact]
+        public override void Result_operator_nav_prop_reference_optional_via_DefaultIfEmpty()
+        {
+            base.Result_operator_nav_prop_reference_optional_via_DefaultIfEmpty();
+
+            AssertSql(
+                @"SELECT SUM(CASE
+    WHEN [t0].[Id] IS NULL
+    THEN 0 ELSE [t0].[OneToOne_Required_PK_Level1_Required_Id]
+END)
+FROM [Level1] AS [l1]
+LEFT JOIN (
+    SELECT [t].*
+    FROM [Level1] AS [t]
+    WHERE [t].[Id] IS NOT NULL
+) AS [t0] ON [l1].[Id] = [t0].[OneToOne_Required_PK_Level1_Optional_Id]");
         }
 
         private void AssertSql(params string[] expected)

test/EFCore.Sqlite.FunctionalTests/Query/ComplexNavigationsOwnedQuerySqliteTest.cs

@@ -18,11 +18,5 @@ public override void Nested_group_join_with_take()
         {
             base.Nested_group_join_with_take();
         }
-
-        [ConditionalFact(Skip = "issue #8492")]
-        public override void Explicit_GroupJoin_in_subquery_with_unrelated_projection2()
-        {
-            base.Explicit_GroupJoin_in_subquery_with_unrelated_projection2();
-        }
     }
 }