From 08cefb32ddec47976d1868189982293d869e7010 Mon Sep 17 00:00:00 2001
From: Shay Rojansky <roji@roji.org>
Date: Tue, 5 Aug 2025 00:24:50 +0200
Subject: [PATCH] Dispose related readers in GroupBySplitQueryingEnumerable
 (#36484) (#36489)

Fixes #34280

(cherry picked from commit 08f094b6823df39d5b2894dbc64f90143e917259)
---
 .../GroupBySplitQueryingEnumerable.cs         | 37 +++++++++++++++----
 .../Query/Internal/SplitQueryingEnumerable.cs |  2 +
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/src/EFCore.Relational/Query/Internal/GroupBySplitQueryingEnumerable.cs b/src/EFCore.Relational/Query/Internal/GroupBySplitQueryingEnumerable.cs
index ae8d9e3e47d..12b16333b33 100644
--- a/src/EFCore.Relational/Query/Internal/GroupBySplitQueryingEnumerable.cs
+++ b/src/EFCore.Relational/Query/Internal/GroupBySplitQueryingEnumerable.cs
@@ -330,6 +330,19 @@ public void Dispose()
             {
                 _relationalQueryContext.Connection.ReturnCommand(_relationalCommand!);
                 _dataReader.Dispose();
+
+                if (_resultCoordinator != null)
+                {
+                    foreach (var dataReader in _resultCoordinator.DataReaders)
+                    {
+                        dataReader?.DataReader.Dispose();
+                    }
+
+                    _resultCoordinator.DataReaders.Clear();
+
+                    _resultCoordinator = null;
+                }
+
                 _dataReader = null;
                 _dbDataReader = null;
             }
@@ -503,20 +516,30 @@ private static async Task<bool> InitializeReaderAsync(AsyncEnumerator enumerator
             return false;
         }
 
-        public ValueTask DisposeAsync()
+        public async ValueTask DisposeAsync()
         {
-            if (_dataReader is not null)
+            if (_dataReader != null)
             {
                 _relationalQueryContext.Connection.ReturnCommand(_relationalCommand!);
+                await _dataReader.DisposeAsync().ConfigureAwait(false);
+
+                if (_resultCoordinator != null)
+                {
+                    foreach (var dataReader in _resultCoordinator.DataReaders)
+                    {
+                        if (dataReader != null)
+                        {
+                            await dataReader.DataReader.DisposeAsync().ConfigureAwait(false);
+                        }
+                    }
+
+                    _resultCoordinator.DataReaders.Clear();
+                    _resultCoordinator = null;
+                }
 
-                var dataReader = _dataReader;
                 _dataReader = null;
                 _dbDataReader = null;
-
-                return dataReader.DisposeAsync();
             }
-
-            return default;
         }
     }
 }
diff --git a/src/EFCore.Relational/Query/Internal/SplitQueryingEnumerable.cs b/src/EFCore.Relational/Query/Internal/SplitQueryingEnumerable.cs
index c87544d1120..830fbb25470 100644
--- a/src/EFCore.Relational/Query/Internal/SplitQueryingEnumerable.cs
+++ b/src/EFCore.Relational/Query/Internal/SplitQueryingEnumerable.cs
@@ -251,6 +251,7 @@ public void Dispose()
             {
                 _relationalQueryContext.Connection.ReturnCommand(_relationalCommand!);
                 _dataReader.Dispose();
+
                 if (_resultCoordinator != null)
                 {
                     foreach (var dataReader in _resultCoordinator.DataReaders)
@@ -407,6 +408,7 @@ public async ValueTask DisposeAsync()
             {
                 _relationalQueryContext.Connection.ReturnCommand(_relationalCommand!);
                 await _dataReader.DisposeAsync().ConfigureAwait(false);
+
                 if (_resultCoordinator != null)
                 {
                     foreach (var dataReader in _resultCoordinator.DataReaders)