diff --git a/src/EFCore.Relational/Query/Internal/NullSemanticsRewritingExpressionVisitor.cs b/src/EFCore.Relational/Query/Internal/NullSemanticsRewritingExpressionVisitor.cs
index 8313988ee26..8d9c1f200c8 100644
--- a/src/EFCore.Relational/Query/Internal/NullSemanticsRewritingExpressionVisitor.cs
+++ b/src/EFCore.Relational/Query/Internal/NullSemanticsRewritingExpressionVisitor.cs
@@ -249,6 +249,16 @@ protected override Expression VisitRowNumber(RowNumberExpression rowNumberExpres
             return rowNumberExpression.Update(partitions, orderings);
         }
 
+        protected override Expression VisitScalarSubquery(ScalarSubqueryExpression scalarSubqueryExpression)
+        {
+            var canOptimize = _canOptimize;
+            _canOptimize = false;
+            var subquery = (SelectExpression)Visit(scalarSubqueryExpression.Subquery);
+            _canOptimize = canOptimize;
+
+            return scalarSubqueryExpression.Update(subquery);
+        }
+
         protected override Expression VisitSelect(SelectExpression selectExpression)
         {
             var changed = false;
@@ -584,16 +594,6 @@ protected override Expression VisitSqlUnary(SqlUnaryExpression sqlCastExpression
             return sqlCastExpression.Update(newOperand);
         }
 
-        protected override Expression VisitSubSelect(ScalarSubqueryExpression scalarSubqueryExpression)
-        {
-            var canOptimize = _canOptimize;
-            _canOptimize = false;
-            var subquery = (SelectExpression)Visit(scalarSubqueryExpression.Subquery);
-            _canOptimize = canOptimize;
-
-            return scalarSubqueryExpression.Update(subquery);
-        }
-
         protected override Expression VisitTable(TableExpression tableExpression)
             => tableExpression;
 
diff --git a/src/EFCore.Relational/Query/QuerySqlGenerator.cs b/src/EFCore.Relational/Query/QuerySqlGenerator.cs
index 2dbb0c227fb..4b605f83b91 100644
--- a/src/EFCore.Relational/Query/QuerySqlGenerator.cs
+++ b/src/EFCore.Relational/Query/QuerySqlGenerator.cs
@@ -732,7 +732,7 @@ protected override Expression VisitLeftJoin(LeftJoinExpression leftJoinExpressio
             return leftJoinExpression;
         }
 
-        protected override Expression VisitSubSelect(ScalarSubqueryExpression scalarSubqueryExpression)
+        protected override Expression VisitScalarSubquery(ScalarSubqueryExpression scalarSubqueryExpression)
         {
             _relationalCommandBuilder.AppendLine("(");
             using (_relationalCommandBuilder.Indent())
diff --git a/src/EFCore.Relational/Query/SqlExpressionVisitor.cs b/src/EFCore.Relational/Query/SqlExpressionVisitor.cs
index c034f4e0f14..bc3ea3cbbfd 100644
--- a/src/EFCore.Relational/Query/SqlExpressionVisitor.cs
+++ b/src/EFCore.Relational/Query/SqlExpressionVisitor.cs
@@ -81,8 +81,8 @@ protected override Expression VisitExtension(Expression extensionExpression)
                 case SqlParameterExpression sqlParameterExpression:
                     return VisitSqlParameter(sqlParameterExpression);
 
-                case ScalarSubqueryExpression subSelectExpression:
-                    return VisitSubSelect(subSelectExpression);
+                case ScalarSubqueryExpression scalarSubqueryExpression:
+                    return VisitScalarSubquery(scalarSubqueryExpression);
 
                 case TableExpression tableExpression:
                     return VisitTable(tableExpression);
@@ -110,14 +110,14 @@ protected override Expression VisitExtension(Expression extensionExpression)
         protected abstract Expression VisitOuterApply(OuterApplyExpression outerApplyExpression);
         protected abstract Expression VisitProjection(ProjectionExpression projectionExpression);
         protected abstract Expression VisitRowNumber(RowNumberExpression rowNumberExpression);
+        protected abstract Expression VisitScalarSubquery(ScalarSubqueryExpression scalarSubqueryExpression);
         protected abstract Expression VisitSelect(SelectExpression selectExpression);
         protected abstract Expression VisitSqlBinary(SqlBinaryExpression sqlBinaryExpression);
         protected abstract Expression VisitSqlConstant(SqlConstantExpression sqlConstantExpression);
         protected abstract Expression VisitSqlFragment(SqlFragmentExpression sqlFragmentExpression);
         protected abstract Expression VisitSqlFunction(SqlFunctionExpression sqlFunctionExpression);
         protected abstract Expression VisitSqlParameter(SqlParameterExpression sqlParameterExpression);
-        protected abstract Expression VisitSqlUnary(SqlUnaryExpression sqlCastExpression);
-        protected abstract Expression VisitSubSelect(ScalarSubqueryExpression scalarSubqueryExpression);
+        protected abstract Expression VisitSqlUnary(SqlUnaryExpression sqlUnaryExpression);
         protected abstract Expression VisitTable(TableExpression tableExpression);
         protected abstract Expression VisitUnion(UnionExpression unionExpression);
     }
diff --git a/src/EFCore.Relational/Query/SqlExpressions/ScalarSubqueryExpression.cs b/src/EFCore.Relational/Query/SqlExpressions/ScalarSubqueryExpression.cs
index 8165da6b9a8..e8d05f45e22 100644
--- a/src/EFCore.Relational/Query/SqlExpressions/ScalarSubqueryExpression.cs
+++ b/src/EFCore.Relational/Query/SqlExpressions/ScalarSubqueryExpression.cs
@@ -50,8 +50,8 @@ public override void Print(ExpressionPrinter expressionPrinter)
         public override bool Equals(object obj)
             => obj != null
                 && (ReferenceEquals(this, obj)
-                    || obj is ScalarSubqueryExpression subSelectExpression
-                    && Equals(subSelectExpression));
+                    || obj is ScalarSubqueryExpression scalarSubqueryExpression
+                    && Equals(scalarSubqueryExpression));
 
         private bool Equals(ScalarSubqueryExpression scalarSubqueryExpression)
             => base.Equals(scalarSubqueryExpression)
diff --git a/src/EFCore.Relational/Query/SqlExpressions/SqlFunctionExpression.cs b/src/EFCore.Relational/Query/SqlExpressions/SqlFunctionExpression.cs
index bcbcad1b49f..a96ba570ac7 100644
--- a/src/EFCore.Relational/Query/SqlExpressions/SqlFunctionExpression.cs
+++ b/src/EFCore.Relational/Query/SqlExpressions/SqlFunctionExpression.cs
@@ -56,7 +56,7 @@ public static SqlFunctionExpression Create(
             => new SqlFunctionExpression(instance: null, schema, name, niladic: false, arguments, builtIn: false, type, typeMapping);
 
         public SqlFunctionExpression(
-            Expression instance,
+            SqlExpression instance,
             string schema,
             string name,
             bool niladic,
@@ -79,7 +79,7 @@ public SqlFunctionExpression(
         public virtual bool IsNiladic { get; }
         public virtual bool IsBuiltIn { get; }
         public virtual IReadOnlyList<SqlExpression> Arguments { get; }
-        public virtual Expression Instance { get; }
+        public virtual SqlExpression Instance { get; }
 
         protected override Expression VisitChildren(ExpressionVisitor visitor)
         {
diff --git a/src/EFCore.SqlServer/Query/Internal/SearchConditionConvertingExpressionVisitor.cs b/src/EFCore.SqlServer/Query/Internal/SearchConditionConvertingExpressionVisitor.cs
index c206cc7ffe5..f578fc5166b 100644
--- a/src/EFCore.SqlServer/Query/Internal/SearchConditionConvertingExpressionVisitor.cs
+++ b/src/EFCore.SqlServer/Query/Internal/SearchConditionConvertingExpressionVisitor.cs
@@ -360,7 +360,7 @@ protected override Expression VisitLeftJoin(LeftJoinExpression leftJoinExpressio
             return leftJoinExpression.Update(table, joinPredicate);
         }
 
-        protected override Expression VisitSubSelect(ScalarSubqueryExpression scalarSubqueryExpression)
+        protected override Expression VisitScalarSubquery(ScalarSubqueryExpression scalarSubqueryExpression)
         {
             var parentSearchCondition = _isSearchCondition;
             var subquery = (SelectExpression)Visit(scalarSubqueryExpression.Subquery);