From 89c2455139e02f0dd50e9b212a5503628d61380d Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 09:07:24 -0400
Subject: [PATCH 01/21] fix(sqlalchemy-spanner): isolate test database names
 and extend stale cleanup cutoff

---
 .../create_test_database.py                   | 35 ++++++++++++-------
 .../sqlalchemy-spanner/drop_test_database.py  | 33 +++++++++++++++--
 2 files changed, 52 insertions(+), 16 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 804bd2936ad2..775d9ac86a2a 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -14,18 +14,19 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import json
 import os
 import re
 import time
+import uuid
 
+from create_test_config import set_test_config
 from google.api_core import datetime_helpers
 from google.api_core.exceptions import AlreadyExists, ResourceExhausted
 from google.cloud.spanner_v1 import Client
 from google.cloud.spanner_v1.database import Database
 from google.cloud.spanner_v1.instance import Instance
 
-from create_test_config import set_test_config
-
 USE_EMULATOR = os.getenv("SPANNER_EMULATOR_HOST") is not None
 
 PROJECT = os.getenv(
@@ -69,26 +70,26 @@ def delete_stale_test_instances():
 
 
 def delete_stale_test_databases():
-    """Delete test databases that are older than 10 minutes.
-    
-    In this test suite, active databases typically finish running in ~5 minutes.
-    To prevent concurrent Kokoro runs from accidentally deleting each other's
-    active databases we use a 10-minute safety threshold. Without an aggressive
-    cutoff we quickly bump up against Cloud Spanner's limit of 100 databases per instance.
+    """Delete test databases that are older than 30 minutes.
+
+    In this test suite, compliance and system test sessions can run for 15-20 minutes.
+    To prevent concurrent Kokoro runs or long compliance test suites from accidentally
+    deleting each other's active databases while still cleaning up orphaned databases
+    to respect Spanner's 100-database limit, we use a 30-minute safety threshold.
     """
-    cutoff = (int(time.time()) - 10 * 60) * 1000
+    cutoff = (int(time.time()) - 30 * 60) * 1000
     instance = CLIENT.instance("sqlalchemy-dialect-test")
     if not instance.exists():
         return
     database_pbs = instance.list_databases()
     for database_pb in database_pbs:
         database = Database.from_pb(database_pb, instance)
-        # Parse creation time from database ID first (e.g. "sqlalchemy-test-1779989493809")
+        # Parse creation time from database ID first (e.g. "sqlalchemy-test-177998949-a1b2")
         # to be 100% independent of emulator metadata or GCP Client API create_time gaps!
         create_time = None
         match = re.match(r"sqlalchemy-test-(\d+)", database.database_id)
         if match:
-            create_time = int(match.group(1))
+            create_time = int(match.group(1)) * 1000
         elif database_pb.create_time is not None:
             create_time = datetime_helpers.to_milliseconds(database_pb.create_time)
 
@@ -123,8 +124,11 @@ def create_test_instance():
         except AlreadyExists:
             pass  # instance was already created
 
-    unique_resource_id = "%s%d" % ("-", 1000 * time.time())
-    database_id = "sqlalchemy-test" + unique_resource_id
+    # Generate a session-isolated unique database ID within Spanner 30-char limit
+    creation_timestamp = time.time()
+    timestamp_part = str(int(creation_timestamp))[-9:]
+    rand_part = uuid.uuid4().hex[:4]
+    database_id = f"sqlalchemy-test-{timestamp_part}-{rand_part}"
 
     try:
         database = instance.database(database_id)
@@ -135,6 +139,11 @@ def create_test_instance():
 
     set_test_config(PROJECT, instance_id, database_id)
 
+    # Record metadata for duration tracking on teardown
+    meta_path = os.path.join(os.path.dirname(__file__), ".db_session_info.json")
+    with open(meta_path, "w") as f:
+        json.dump({"database_id": database_id, "creation_time": creation_timestamp}, f)
+
 
 delete_stale_test_databases()
 create_test_instance()
diff --git a/packages/sqlalchemy-spanner/drop_test_database.py b/packages/sqlalchemy-spanner/drop_test_database.py
index b7facf1f9ea1..9da95e0cd0b5 100644
--- a/packages/sqlalchemy-spanner/drop_test_database.py
+++ b/packages/sqlalchemy-spanner/drop_test_database.py
@@ -15,18 +15,18 @@
 # limitations under the License.
 
 import configparser
+import json
 import os
 import re
 import time
 
+from create_test_config import set_test_config
 from google.api_core import datetime_helpers
 from google.api_core.exceptions import AlreadyExists, ResourceExhausted
 from google.cloud.spanner_v1 import Client
 from google.cloud.spanner_v1.database import Database
 from google.cloud.spanner_v1.instance import Instance
 
-from create_test_config import set_test_config
-
 USE_EMULATOR = os.getenv("SPANNER_EMULATOR_HOST") is not None
 
 PROJECT = os.getenv(
@@ -43,6 +43,15 @@
     CLIENT = Client(project=PROJECT)
 
 
+def format_duration(seconds):
+    mins = int(seconds // 60)
+    secs = int(seconds % 60)
+    if mins > 0:
+        return f"{mins} minutes and {secs} seconds"
+    else:
+        return f"{secs} seconds"
+
+
 def delete_test_database():
     """Delete the currently configured test database."""
     config = configparser.ConfigParser()
@@ -56,8 +65,26 @@ def delete_test_database():
     database_id = re.findall(r"databases(.*?)$", db_url)
 
     instance = CLIENT.instance(instance_id="".join(instance_id).replace("/", ""))
-    database = instance.database("".join(database_id).replace("/", ""))
+    database_id_str = "".join(database_id).replace("/", "")
+    database = instance.database(database_id_str)
     database.drop()
 
+    # Calculate and report active duration
+    meta_path = os.path.join(os.path.dirname(__file__), ".db_session_info.json")
+    if os.path.exists(meta_path):
+        try:
+            with open(meta_path, "r") as f:
+                meta = json.load(f)
+            creation_time = meta.get("creation_time", time.time())
+            db_name = meta.get("database_id", database_id_str)
+            elapsed_seconds = time.time() - creation_time
+            duration_str = format_duration(elapsed_seconds)
+            print(f"[Spanner DB] Database {db_name} was active for {duration_str} before teardown.")
+        except Exception:
+            pass
+        finally:
+            if os.path.exists(meta_path):
+                os.remove(meta_path)
+
 
 delete_test_database()

From ec9200fb6f98e224ba602050faa1c32dcb594f1e Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 09:37:45 -0400
Subject: [PATCH 02/21] fix(sqlalchemy-spanner): retain full 10-digit timestamp
 in db name and validate metadata dict type

---
 .../sqlalchemy-spanner/create_test_database.py   | 16 +++++++++++-----
 .../sqlalchemy-spanner/drop_test_database.py     | 13 +++++++------
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 775d9ac86a2a..2b93e0799b83 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -84,12 +84,17 @@ def delete_stale_test_databases():
     database_pbs = instance.list_databases()
     for database_pb in database_pbs:
         database = Database.from_pb(database_pb, instance)
-        # Parse creation time from database ID first (e.g. "sqlalchemy-test-177998949-a1b2")
-        # to be 100% independent of emulator metadata or GCP Client API create_time gaps!
+        # Parse creation time from database ID first (e.g. "sqlalchemy-test-1787069488-a3f")
+        # handling both 10-digit (seconds) and 13-digit (milliseconds) timestamps robustly.
         create_time = None
         match = re.match(r"sqlalchemy-test-(\d+)", database.database_id)
         if match:
-            create_time = int(match.group(1)) * 1000
+            ts_str = match.group(1)
+            ts_val = int(ts_str)
+            if len(ts_str) == 10:
+                create_time = ts_val * 1000
+            else:
+                create_time = ts_val
         elif database_pb.create_time is not None:
             create_time = datetime_helpers.to_milliseconds(database_pb.create_time)
 
@@ -125,9 +130,10 @@ def create_test_instance():
             pass  # instance was already created
 
     # Generate a session-isolated unique database ID within Spanner 30-char limit
+    # Format: sqlalchemy-test-{timestamp_in_seconds}-{rand_hex3} (exactly 30 characters total)
     creation_timestamp = time.time()
-    timestamp_part = str(int(creation_timestamp))[-9:]
-    rand_part = uuid.uuid4().hex[:4]
+    timestamp_part = str(int(creation_timestamp))
+    rand_part = uuid.uuid4().hex[:3]
     database_id = f"sqlalchemy-test-{timestamp_part}-{rand_part}"
 
     try:
diff --git a/packages/sqlalchemy-spanner/drop_test_database.py b/packages/sqlalchemy-spanner/drop_test_database.py
index 9da95e0cd0b5..35bb17f9cd29 100644
--- a/packages/sqlalchemy-spanner/drop_test_database.py
+++ b/packages/sqlalchemy-spanner/drop_test_database.py
@@ -69,17 +69,18 @@ def delete_test_database():
     database = instance.database(database_id_str)
     database.drop()
 
-    # Calculate and report active duration
+    # Calculate and report active duration with type-validation for compliance
     meta_path = os.path.join(os.path.dirname(__file__), ".db_session_info.json")
     if os.path.exists(meta_path):
         try:
             with open(meta_path, "r") as f:
                 meta = json.load(f)
-            creation_time = meta.get("creation_time", time.time())
-            db_name = meta.get("database_id", database_id_str)
-            elapsed_seconds = time.time() - creation_time
-            duration_str = format_duration(elapsed_seconds)
-            print(f"[Spanner DB] Database {db_name} was active for {duration_str} before teardown.")
+            if isinstance(meta, dict):
+                creation_time = meta.get("creation_time", time.time())
+                db_name = meta.get("database_id", database_id_str)
+                elapsed_seconds = time.time() - creation_time
+                duration_str = format_duration(elapsed_seconds)
+                print(f"[Spanner DB] Database {db_name} was active for {duration_str} before teardown.")
         except Exception:
             pass
         finally:

From fa9ca91c91d5c5f44a8b98545972b8b7e2afbadc Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 10:04:10 -0400
Subject: [PATCH 03/21] fix(sqlalchemy-spanner): protect active test database
 from accidental garbage collection

---
 .../create_test_database.py                   | 27 ++++++++++++++-----
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 2b93e0799b83..7b986ebf4492 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -14,6 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import configparser
 import json
 import os
 import re
@@ -70,13 +71,22 @@ def delete_stale_test_instances():
 
 
 def delete_stale_test_databases():
-    """Delete test databases that are older than 30 minutes.
-
-    In this test suite, compliance and system test sessions can run for 15-20 minutes.
-    To prevent concurrent Kokoro runs or long compliance test suites from accidentally
-    deleting each other's active databases while still cleaning up orphaned databases
-    to respect Spanner's 100-database limit, we use a 30-minute safety threshold.
+    """Delete test databases that are older than 30 minutes,
+    excluding the currently active test database.
     """
+    # Read currently configured active database from test.cfg if it exists
+    active_db_id = None
+    config_path = os.path.join(os.path.dirname(__file__), "test.cfg")
+    if os.path.exists(config_path):
+        try:
+            cfg = configparser.ConfigParser()
+            cfg.read(config_path)
+            db_url = cfg.get("db", "default", fallback="")
+            if "databases/" in db_url:
+                active_db_id = db_url.split("databases/")[-1].split("?")[0]
+        except Exception:
+            pass
+
     cutoff = (int(time.time()) - 30 * 60) * 1000
     instance = CLIENT.instance("sqlalchemy-dialect-test")
     if not instance.exists():
@@ -84,6 +94,11 @@ def delete_stale_test_databases():
     database_pbs = instance.list_databases()
     for database_pb in database_pbs:
         database = Database.from_pb(database_pb, instance)
+
+        # NEVER drop the currently active database configured in test.cfg
+        if active_db_id and database.database_id == active_db_id:
+            continue
+
         # Parse creation time from database ID first (e.g. "sqlalchemy-test-1787069488-a3f")
         # handling both 10-digit (seconds) and 13-digit (milliseconds) timestamps robustly.
         create_time = None

From 774d4f414d0ef18159dc2356979a548a876df507 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 10:23:55 -0400
Subject: [PATCH 04/21] fix(sqlalchemy-spanner): remove test.cfg lookup in
 cleanup and use generous 1-hour cutoff

---
 .../create_test_database.py                   | 29 +++++--------------
 1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 7b986ebf4492..3d49c2083c4a 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -14,7 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import configparser
 import json
 import os
 import re
@@ -71,23 +70,15 @@ def delete_stale_test_instances():
 
 
 def delete_stale_test_databases():
-    """Delete test databases that are older than 30 minutes,
-    excluding the currently active test database.
+    """Delete test databases that are older than 1 hour.
+
+    Since each test run creates a 100% session-isolated database with a unique
+    timestamp in its name (`sqlalchemy-test-{timestamp}-{rand}`), concurrent runs
+    never collide. We use a generous 1-hour safety cutoff to clean up orphaned
+    databases from crashed/abandoned runs while ensuring active test runs
+    (even long compliance suites) are naturally protected by their recent timestamps.
     """
-    # Read currently configured active database from test.cfg if it exists
-    active_db_id = None
-    config_path = os.path.join(os.path.dirname(__file__), "test.cfg")
-    if os.path.exists(config_path):
-        try:
-            cfg = configparser.ConfigParser()
-            cfg.read(config_path)
-            db_url = cfg.get("db", "default", fallback="")
-            if "databases/" in db_url:
-                active_db_id = db_url.split("databases/")[-1].split("?")[0]
-        except Exception:
-            pass
-
-    cutoff = (int(time.time()) - 30 * 60) * 1000
+    cutoff = (int(time.time()) - 60 * 60) * 1000
     instance = CLIENT.instance("sqlalchemy-dialect-test")
     if not instance.exists():
         return
@@ -95,10 +86,6 @@ def delete_stale_test_databases():
     for database_pb in database_pbs:
         database = Database.from_pb(database_pb, instance)
 
-        # NEVER drop the currently active database configured in test.cfg
-        if active_db_id and database.database_id == active_db_id:
-            continue
-
         # Parse creation time from database ID first (e.g. "sqlalchemy-test-1787069488-a3f")
         # handling both 10-digit (seconds) and 13-digit (milliseconds) timestamps robustly.
         create_time = None

From 1bad94e404678fd43e517fecb5673923c36def71 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 12:02:14 -0400
Subject: [PATCH 05/21] fix(sqlalchemy-spanner): align database cleanup cutoff
 with 4-hour instance threshold

---
 .../sqlalchemy-spanner/create_test_database.py  | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 3d49c2083c4a..67025682ec92 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -70,15 +70,16 @@ def delete_stale_test_instances():
 
 
 def delete_stale_test_databases():
-    """Delete test databases that are older than 1 hour.
-
-    Since each test run creates a 100% session-isolated database with a unique
-    timestamp in its name (`sqlalchemy-test-{timestamp}-{rand}`), concurrent runs
-    never collide. We use a generous 1-hour safety cutoff to clean up orphaned
-    databases from crashed/abandoned runs while ensuring active test runs
-    (even long compliance suites) are naturally protected by their recent timestamps.
+    """Delete test databases that are older than 4 hours.
+
+    Compliance test suites can take up to 2 hours to run fully. To prevent long-running
+    compliance test sessions from hitting their own cleanup threshold mid-test, we align
+    the database cleanup cutoff with test instances at 4 hours. Combined with
+    session-isolated names (`sqlalchemy-test-{timestamp}-{rand}`), active test runs
+    are completely safe while abandoned databases are still cleaned up well before
+    reaching Spanner's 100-database limit.
     """
-    cutoff = (int(time.time()) - 60 * 60) * 1000
+    cutoff = (int(time.time()) - 4 * 60 * 60) * 1000
     instance = CLIENT.instance("sqlalchemy-dialect-test")
     if not instance.exists():
         return

From c95ec89e0f0b220cbddb3db9ac5f6d8549e4d2c2 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 12:09:40 -0400
Subject: [PATCH 06/21] fix(sqlalchemy-spanner): eliminate startup stale
 database cleanup to prevent cross-session drops

---
 .../create_test_database.py                   | 48 -------------------
 1 file changed, 48 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 67025682ec92..8fdff5010cd7 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -16,15 +16,12 @@
 
 import json
 import os
-import re
 import time
 import uuid
 
 from create_test_config import set_test_config
-from google.api_core import datetime_helpers
 from google.api_core.exceptions import AlreadyExists, ResourceExhausted
 from google.cloud.spanner_v1 import Client
-from google.cloud.spanner_v1.database import Database
 from google.cloud.spanner_v1.instance import Instance
 
 USE_EMULATOR = os.getenv("SPANNER_EMULATOR_HOST") is not None
@@ -69,50 +66,6 @@ def delete_stale_test_instances():
             )
 
 
-def delete_stale_test_databases():
-    """Delete test databases that are older than 4 hours.
-
-    Compliance test suites can take up to 2 hours to run fully. To prevent long-running
-    compliance test sessions from hitting their own cleanup threshold mid-test, we align
-    the database cleanup cutoff with test instances at 4 hours. Combined with
-    session-isolated names (`sqlalchemy-test-{timestamp}-{rand}`), active test runs
-    are completely safe while abandoned databases are still cleaned up well before
-    reaching Spanner's 100-database limit.
-    """
-    cutoff = (int(time.time()) - 4 * 60 * 60) * 1000
-    instance = CLIENT.instance("sqlalchemy-dialect-test")
-    if not instance.exists():
-        return
-    database_pbs = instance.list_databases()
-    for database_pb in database_pbs:
-        database = Database.from_pb(database_pb, instance)
-
-        # Parse creation time from database ID first (e.g. "sqlalchemy-test-1787069488-a3f")
-        # handling both 10-digit (seconds) and 13-digit (milliseconds) timestamps robustly.
-        create_time = None
-        match = re.match(r"sqlalchemy-test-(\d+)", database.database_id)
-        if match:
-            ts_str = match.group(1)
-            ts_val = int(ts_str)
-            if len(ts_str) == 10:
-                create_time = ts_val * 1000
-            else:
-                create_time = ts_val
-        elif database_pb.create_time is not None:
-            create_time = datetime_helpers.to_milliseconds(database_pb.create_time)
-
-        if create_time is None or create_time > cutoff:
-            continue
-        try:
-            database.drop()
-        except ResourceExhausted:
-            print(
-                "Unable to drop stale database '{}'. May need manual delete.".format(
-                    database.database_id
-                )
-            )
-
-
 def create_test_instance():
     instance_id = "sqlalchemy-dialect-test"
     instance = CLIENT.instance(instance_id)
@@ -154,5 +107,4 @@ def create_test_instance():
         json.dump({"database_id": database_id, "creation_time": creation_timestamp}, f)
 
 
-delete_stale_test_databases()
 create_test_instance()

From 0ff675477d044ac240f965c6680919ccdc9c00b4 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 13:08:11 -0400
Subject: [PATCH 07/21] fix(sqlalchemy-spanner): add sentinel-guarded 4-hour
 stale database cleanup

---
 .../create_test_database.py                   | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 8fdff5010cd7..9de84456847f 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -16,12 +16,16 @@
 
 import json
 import os
+import pathlib
+import re
 import time
 import uuid
 
 from create_test_config import set_test_config
+from google.api_core import datetime_helpers
 from google.api_core.exceptions import AlreadyExists, ResourceExhausted
 from google.cloud.spanner_v1 import Client
+from google.cloud.spanner_v1.database import Database
 from google.cloud.spanner_v1.instance import Instance
 
 USE_EMULATOR = os.getenv("SPANNER_EMULATOR_HOST") is not None
@@ -66,6 +70,55 @@ def delete_stale_test_instances():
             )
 
 
+def delete_stale_test_databases():
+    """Delete test databases that are older than 4 hours.
+
+    Uses a .stale_cleanup_done sentinel file gate to ensure this global sweep
+    runs exactly once at the start of a test run across parallel/parametrized sessions,
+    preventing concurrent sessions from interfering with each other.
+    """
+    marker = ".stale_cleanup_done"
+    if os.path.exists(marker):
+        return
+
+    try:
+        pathlib.Path(marker).touch(exist_ok=False)
+    except FileExistsError:
+        return  # Another parallel process already performed cleanup
+
+    cutoff = (int(time.time()) - 4 * 60 * 60) * 1000
+    instance = CLIENT.instance("sqlalchemy-dialect-test")
+    if not instance.exists():
+        return
+    database_pbs = instance.list_databases()
+    for database_pb in database_pbs:
+        database = Database.from_pb(database_pb, instance)
+
+        # Parse creation time from database ID first (e.g. "sqlalchemy-test-1787069488-a3f")
+        create_time = None
+        match = re.match(r"sqlalchemy-test-(\d+)", database.database_id)
+        if match:
+            ts_str = match.group(1)
+            ts_val = int(ts_str)
+            if len(ts_str) == 10:
+                create_time = ts_val * 1000
+            else:
+                create_time = ts_val
+        elif database_pb.create_time is not None:
+            create_time = datetime_helpers.to_milliseconds(database_pb.create_time)
+
+        if create_time is None or create_time > cutoff:
+            continue
+        try:
+            database.drop()
+        except ResourceExhausted:
+            print(
+                "Unable to drop stale database '{}'. May need manual delete.".format(
+                    database.database_id
+                )
+            )
+
+
 def create_test_instance():
     instance_id = "sqlalchemy-dialect-test"
     instance = CLIENT.instance(instance_id)
@@ -107,4 +160,5 @@ def create_test_instance():
         json.dump({"database_id": database_id, "creation_time": creation_timestamp}, f)
 
 
+delete_stale_test_databases()
 create_test_instance()

From 8057ab53121ae50b2156b1b148e34443ea366db1 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 13:54:08 -0400
Subject: [PATCH 08/21] fix(sqlalchemy-spanner): isolate test config per nox
 session to prevent cross-session database drops

---
 .../sqlalchemy-spanner/create_test_config.py  |  4 +-
 .../sqlalchemy-spanner/drop_test_database.py  | 12 ++-
 packages/sqlalchemy-spanner/noxfile.py        | 98 +++++++++++--------
 packages/sqlalchemy-spanner/tests/_helpers.py |  7 +-
 4 files changed, 76 insertions(+), 45 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_config.py b/packages/sqlalchemy-spanner/create_test_config.py
index 3ca1ab9bce88..1917e199a90d 100644
--- a/packages/sqlalchemy-spanner/create_test_config.py
+++ b/packages/sqlalchemy-spanner/create_test_config.py
@@ -15,6 +15,7 @@
 # limitations under the License.
 
 import configparser
+import os
 import sys
 
 
@@ -41,7 +42,8 @@ def set_test_config(
     config.add_section("db")
     config["db"]["default"] = url
 
-    with open("test.cfg", "w") as configfile:
+    config_filename = os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+    with open(config_filename, "w") as configfile:
         config.write(configfile)
 
 
diff --git a/packages/sqlalchemy-spanner/drop_test_database.py b/packages/sqlalchemy-spanner/drop_test_database.py
index 35bb17f9cd29..399d33abcb47 100644
--- a/packages/sqlalchemy-spanner/drop_test_database.py
+++ b/packages/sqlalchemy-spanner/drop_test_database.py
@@ -55,7 +55,10 @@ def format_duration(seconds):
 def delete_test_database():
     """Delete the currently configured test database."""
     config = configparser.ConfigParser()
-    if os.path.exists("test.cfg"):
+    config_filename = os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+    if os.path.exists(config_filename):
+        config.read(config_filename)
+    elif os.path.exists("test.cfg"):
         config.read("test.cfg")
     else:
         config.read("setup.cfg")
@@ -87,5 +90,12 @@ def delete_test_database():
             if os.path.exists(meta_path):
                 os.remove(meta_path)
 
+    # Clean up session-specific config file
+    if os.path.exists(config_filename) and config_filename != "setup.cfg":
+        try:
+            os.remove(config_filename)
+        except Exception:
+            pass
+
 
 delete_test_database()
diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index a69e9bb2b89b..38119c687fed 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -179,6 +179,8 @@ def lint_setup_py(session):
 @nox.session(python=UNIT_TEST_PYTHON_VERSIONS[0])
 def compliance_test_14(session):
     """Run SQLAlchemy dialect compliance test suite."""
+    config_file = f"test_compliance_test_14_{session.python}.cfg"
+    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_file
 
     # Check the value of `RUN_COMPLIANCE_TESTS` env var. It defaults to true.
     if os.environ.get("RUN_COMPLIANCE_TESTS", "true") == "false":
@@ -191,34 +193,42 @@ def compliance_test_14(session):
             "Credentials or emulator host must be set via environment variable"
         )
 
-    session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
-    session.install(".[tracing]")
-    session.run(
-        "pip",
-        "install",
-        *SQLALCHEMY_14_DEPENDENCIES,
-        "--force-reinstall",
-    )
-    session.run("python", "create_test_database.py")
-    session.run(
-        "py.test",
-        "--cov=google.cloud.sqlalchemy_spanner",
-        "--cov=tests",
-        "--cov-append",
-        "--cov-config=.coveragerc",
-        "--cov-report=",
-        "--cov-fail-under=0",
-        "--asyncio-mode=auto",
-        "tests/test_suite_14.py",
-        *session.posargs,
-        # Silence SQLAlchemy 2.0 transition warnings for this 1.4 compatibility session.
-        env={"SQLALCHEMY_SILENCE_UBER_WARNING": "1"},
-    )
+    try:
+        session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
+        session.install(".[tracing]")
+        session.run(
+            "pip",
+            "install",
+            *SQLALCHEMY_14_DEPENDENCIES,
+            "--force-reinstall",
+        )
+        session.run("python", "create_test_database.py")
+        session.run(
+            "py.test",
+            "--cov=google.cloud.sqlalchemy_spanner",
+            "--cov=tests",
+            "--cov-append",
+            "--cov-config=.coveragerc",
+            "--cov-report=",
+            "--cov-fail-under=0",
+            "--asyncio-mode=auto",
+            "tests/test_suite_14.py",
+            *session.posargs,
+            # Silence SQLAlchemy 2.0 transition warnings for this 1.4 compatibility session.
+            env={"SQLALCHEMY_SILENCE_UBER_WARNING": "1"},
+        )
+    finally:
+        if os.path.exists(config_file):
+            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+        elif os.path.exists("test.cfg"):
+            session.run("python", "drop_test_database.py", success_codes=[0, 1])
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION_FOR_SQLALCHEMY_20)
 def compliance_test_20(session):
     """Run SQLAlchemy dialect compliance test suite."""
+    config_file = f"test_compliance_test_20_{session.python}.cfg"
+    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_file
 
     # Check the value of `RUN_COMPLIANCE_TESTS` env var. It defaults to true.
     if os.environ.get("RUN_COMPLIANCE_TESTS", "true") == "false":
@@ -232,24 +242,30 @@ def compliance_test_20(session):
             "Credentials or emulator host must be set via environment variable"
         )
 
-    session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
-    session.install("-e", ".", "--force-reinstall")
-    session.run("python", "create_test_database.py")
-
-    session.install(*SQLALCHEMY_20_DEPENDENCIES)
-
-    session.run(
-        "py.test",
-        "--cov=google.cloud.sqlalchemy_spanner",
-        "--cov=tests",
-        "--cov-append",
-        "--cov-config=.coveragerc",
-        "--cov-report=",
-        "--cov-fail-under=0",
-        "--asyncio-mode=auto",
-        "tests/test_suite_20.py",
-        *session.posargs,
-    )
+    try:
+        session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
+        session.install("-e", ".", "--force-reinstall")
+        session.run("python", "create_test_database.py")
+
+        session.install(*SQLALCHEMY_20_DEPENDENCIES)
+
+        session.run(
+            "py.test",
+            "--cov=google.cloud.sqlalchemy_spanner",
+            "--cov=tests",
+            "--cov-append",
+            "--cov-config=.coveragerc",
+            "--cov-report=",
+            "--cov-fail-under=0",
+            "--asyncio-mode=auto",
+            "tests/test_suite_20.py",
+            *session.posargs,
+        )
+    finally:
+        if os.path.exists(config_file):
+            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+        elif os.path.exists("test.cfg"):
+            session.run("python", "drop_test_database.py", success_codes=[0, 1])
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION_FOR_SQLALCHEMY_20)
diff --git a/packages/sqlalchemy-spanner/tests/_helpers.py b/packages/sqlalchemy-spanner/tests/_helpers.py
index 40673b2607cb..8feea107acc0 100644
--- a/packages/sqlalchemy-spanner/tests/_helpers.py
+++ b/packages/sqlalchemy-spanner/tests/_helpers.py
@@ -44,9 +44,12 @@
 
 def get_db_url():
     config = configparser.ConfigParser()
-    if os.path.exists("test.cfg"):
+    config_filename = os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+    if os.path.exists(config_filename):
+        config.read(config_filename)
+    elif os.path.exists("test.cfg"):
         config.read("test.cfg")
-    else:
+    elif os.path.exists("setup.cfg"):
         config.read("setup.cfg")
     return config.get("db", "default", fallback=DB_URL)
 

From a7cfa9cd81872bd30a73d6cfd6cb262872c37f48 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 14:40:56 -0400
Subject: [PATCH 09/21] fix(sqlalchemy-spanner): explicitly pass --dburi to
 pytest to prevent fallback to sqlite

---
 packages/sqlalchemy-spanner/noxfile.py | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index 38119c687fed..1f5995541186 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -203,8 +203,12 @@ def compliance_test_14(session):
             "--force-reinstall",
         )
         session.run("python", "create_test_database.py")
+        config = configparser.ConfigParser()
+        config.read(config_file)
+        db_url = config.get("db", "default")
         session.run(
             "py.test",
+            f"--dburi={db_url}",
             "--cov=google.cloud.sqlalchemy_spanner",
             "--cov=tests",
             "--cov-append",
@@ -246,11 +250,15 @@ def compliance_test_20(session):
         session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
         session.install("-e", ".", "--force-reinstall")
         session.run("python", "create_test_database.py")
+        config = configparser.ConfigParser()
+        config.read(config_file)
+        db_url = config.get("db", "default")
 
         session.install(*SQLALCHEMY_20_DEPENDENCIES)
 
         session.run(
             "py.test",
+            f"--dburi={db_url}",
             "--cov=google.cloud.sqlalchemy_spanner",
             "--cov=tests",
             "--cov-append",
@@ -440,9 +448,12 @@ def system(session, test_type):
             session.install(".[tracing]")
             session.install(*SYSTEM_TEST_EXTERNAL_DEPENDENCIES)
             session.run("python", "create_test_database.py")
+            config = configparser.ConfigParser()
+            config.read(config_file)
+            db_url = config.get("db", "default")
             session.install(*SQLALCHEMY_20_DEPENDENCIES)
             session.run(
-                "py.test", "--quiet", os.path.join("tests", "system"), *session.posargs
+                "py.test", f"--dburi={db_url}", "--quiet", os.path.join("tests", "system"), *session.posargs
             )
         elif test_type == "compliance_14":
             compliance_test_14(session)
@@ -453,7 +464,9 @@ def system(session, test_type):
         elif test_type == "migration_20":
             _migration_test(session)
     finally:
-        if os.path.exists("test.cfg"):
+        if os.path.exists(config_file):
+            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+        elif os.path.exists("test.cfg"):
             session.run("python", "drop_test_database.py", success_codes=[0, 1])
 
 

From d7df95e458b9d3317ee985932dfb09c9f82721d2 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 16:12:02 -0400
Subject: [PATCH 10/21] fix(sqlalchemy-spanner): define config_file in system
 session scope to avoid NameError

---
 packages/sqlalchemy-spanner/noxfile.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index 1f5995541186..447bbed3f2ea 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -413,6 +413,9 @@ def unit(session, test_type):
 def system(session, test_type):
     """Run SQLAlchemy dialect system test suite."""
 
+    config_file = f"test_{test_type}_{session.python}.cfg"
+    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_file
+
     if not os.environ.get("GOOGLE_APPLICATION_CREDENTIALS", "") and not os.environ.get(
         "SPANNER_EMULATOR_HOST", ""
     ):

From b2fbe29b044b9d9eba0bc58485e59808e7e60c9c Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Wed, 19 Aug 2026 17:06:11 -0400
Subject: [PATCH 11/21] fix(sqlalchemy-spanner): use Spanner-compliant database
 ID format with underscores instead of hyphens

---
 packages/sqlalchemy-spanner/create_test_database.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 9de84456847f..4fbb2851d808 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -94,9 +94,9 @@ def delete_stale_test_databases():
     for database_pb in database_pbs:
         database = Database.from_pb(database_pb, instance)
 
-        # Parse creation time from database ID first (e.g. "sqlalchemy-test-1787069488-a3f")
+        # Parse creation time from database ID first (e.g. "sp_test_1787069488_a3f")
         create_time = None
-        match = re.match(r"sqlalchemy-test-(\d+)", database.database_id)
+        match = re.match(r"sp_test_(\d+)", database.database_id)
         if match:
             ts_str = match.group(1)
             ts_val = int(ts_str)
@@ -139,11 +139,11 @@ def create_test_instance():
             pass  # instance was already created
 
     # Generate a session-isolated unique database ID within Spanner 30-char limit
-    # Format: sqlalchemy-test-{timestamp_in_seconds}-{rand_hex3} (exactly 30 characters total)
+    # Format: sp_test_{timestamp_in_seconds}_{rand_hex3} (compliant with Spanner naming: ^[a-z][a-z0-9_]{1,29}$)
     creation_timestamp = time.time()
     timestamp_part = str(int(creation_timestamp))
     rand_part = uuid.uuid4().hex[:3]
-    database_id = f"sqlalchemy-test-{timestamp_part}-{rand_part}"
+    database_id = f"sp_test_{timestamp_part}_{rand_part}"
 
     try:
         database = instance.database(database_id)

From 3e0edae5b0610776d7aeb735888a8c34f1413525 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 04:57:53 -0400
Subject: [PATCH 12/21] fix(sqlalchemy-spanner): make _migration_test respect
 SQLALCHEMY_SPANNER_CONFIG instead of falling back to sqlite

---
 packages/sqlalchemy-spanner/noxfile.py | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index 447bbed3f2ea..22d4ca23959f 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -324,13 +324,17 @@ def _migration_test(session):
     import os
     import shutil
 
+    config_file = os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+
     session.install(*MIGRATION_TEST_DEPENDENCIES)
     session.install(".")
 
     session.run("python", "create_test_database.py")
 
     config = configparser.ConfigParser()
-    if os.path.exists("test.cfg"):
+    if os.path.exists(config_file):
+        config.read(config_file)
+    elif os.path.exists("test.cfg"):
         config.read("test.cfg")
     else:
         config.read("setup.cfg")
@@ -366,7 +370,9 @@ def _migration_test(session):
     os.remove("alembic.ini")
     shutil.rmtree("test_migration")
     session.run("python", "migration_test_cleanup.py", db_url)
-    if os.path.exists("test.cfg"):
+    if os.path.exists(config_file) and config_file != "setup.cfg":
+        os.remove(config_file)
+    elif os.path.exists("test.cfg"):
         os.remove("test.cfg")
 
 

From e6399286ddc789756697fd593b693010696a8769 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 05:02:38 -0400
Subject: [PATCH 13/21] style(sqlalchemy-spanner): format noxfile.py with ruff

---
 packages/sqlalchemy-spanner/noxfile.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index 22d4ca23959f..b04f44c61268 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -462,7 +462,11 @@ def system(session, test_type):
             db_url = config.get("db", "default")
             session.install(*SQLALCHEMY_20_DEPENDENCIES)
             session.run(
-                "py.test", f"--dburi={db_url}", "--quiet", os.path.join("tests", "system"), *session.posargs
+                "py.test",
+                f"--dburi={db_url}",
+                "--quiet",
+                os.path.join("tests", "system"),
+                *session.posargs,
             )
         elif test_type == "compliance_14":
             compliance_test_14(session)

From bbeabf52f17e3f6285df1140cc7eca1e2ed35b41 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 06:42:55 -0400
Subject: [PATCH 14/21] fix(tests): improve database isolation and cleanup in
 nox sessions

---
 .../sqlalchemy-spanner/drop_test_database.py  | 19 +++-
 packages/sqlalchemy-spanner/noxfile.py        | 93 ++++++++++---------
 2 files changed, 64 insertions(+), 48 deletions(-)

diff --git a/packages/sqlalchemy-spanner/drop_test_database.py b/packages/sqlalchemy-spanner/drop_test_database.py
index 399d33abcb47..aa27569a575c 100644
--- a/packages/sqlalchemy-spanner/drop_test_database.py
+++ b/packages/sqlalchemy-spanner/drop_test_database.py
@@ -55,14 +55,23 @@ def format_duration(seconds):
 def delete_test_database():
     """Delete the currently configured test database."""
     config = configparser.ConfigParser()
-    config_filename = os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
-    if os.path.exists(config_filename):
-        config.read(config_filename)
+    config_env_val = os.getenv("SQLALCHEMY_SPANNER_CONFIG")
+    if config_env_val:
+        config_filename = config_env_val
+        if not os.path.exists(config_filename):
+            print(f"[Spanner DB] Config file {config_filename} specified in SQLALCHEMY_SPANNER_CONFIG does not exist. Skipping database drop.")
+            return
     elif os.path.exists("test.cfg"):
-        config.read("test.cfg")
+        config_filename = "test.cfg"
     else:
-        config.read("setup.cfg")
+        config_filename = "setup.cfg"
+
+    config.read(config_filename)
+
     db_url = config.get("db", "default")
+    if not db_url.startswith("spanner"):
+        print(f"[Spanner DB] Database URL {db_url} is not a Spanner URL. Skipping database drop.")
+        return
 
     instance_id = re.findall(r"instances(.*?)databases", db_url)
     database_id = re.findall(r"databases(.*?)$", db_url)
diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index b04f44c61268..c385da703cd9 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -179,8 +179,9 @@ def lint_setup_py(session):
 @nox.session(python=UNIT_TEST_PYTHON_VERSIONS[0])
 def compliance_test_14(session):
     """Run SQLAlchemy dialect compliance test suite."""
-    config_file = f"test_compliance_test_14_{session.python}.cfg"
-    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_file
+    config_file = os.environ.setdefault(
+        "SQLALCHEMY_SPANNER_CONFIG", f"test_compliance_14_{session.python}.cfg"
+    )
 
     # Check the value of `RUN_COMPLIANCE_TESTS` env var. It defaults to true.
     if os.environ.get("RUN_COMPLIANCE_TESTS", "true") == "false":
@@ -231,8 +232,9 @@ def compliance_test_14(session):
 @nox.session(python=DEFAULT_PYTHON_VERSION_FOR_SQLALCHEMY_20)
 def compliance_test_20(session):
     """Run SQLAlchemy dialect compliance test suite."""
-    config_file = f"test_compliance_test_20_{session.python}.cfg"
-    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_file
+    config_file = os.environ.setdefault(
+        "SQLALCHEMY_SPANNER_CONFIG", f"test_compliance_20_{session.python}.cfg"
+    )
 
     # Check the value of `RUN_COMPLIANCE_TESTS` env var. It defaults to true.
     if os.environ.get("RUN_COMPLIANCE_TESTS", "true") == "false":
@@ -324,56 +326,60 @@ def _migration_test(session):
     import os
     import shutil
 
-    config_file = os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+    config_file = os.environ.setdefault(
+        "SQLALCHEMY_SPANNER_CONFIG", f"test_migration_{session.python}.cfg"
+    )
 
     session.install(*MIGRATION_TEST_DEPENDENCIES)
     session.install(".")
 
-    session.run("python", "create_test_database.py")
+    try:
+        session.run("python", "create_test_database.py")
 
-    config = configparser.ConfigParser()
-    if os.path.exists(config_file):
-        config.read(config_file)
-    elif os.path.exists("test.cfg"):
-        config.read("test.cfg")
-    else:
-        config.read("setup.cfg")
-    db_url = config.get("db", "default")
+        config = configparser.ConfigParser()
+        if os.path.exists(config_file):
+            config.read(config_file)
+        else:
+            config.read("setup.cfg")
+        db_url = config.get("db", "default")
 
-    session.run("alembic", "init", "test_migration")
+        session.run("alembic", "init", "test_migration")
 
-    # setting testing configurations
-    os.remove("alembic.ini")
-    with open("alembic.ini", "w") as f:
-        f.write(ALEMBIC_CONF.format(db_url))
+        # setting testing configurations
+        if os.path.exists("alembic.ini"):
+            os.remove("alembic.ini")
+        with open("alembic.ini", "w") as f:
+            f.write(ALEMBIC_CONF.format(db_url))
 
-    session.run("alembic", "revision", "-m", "migration_for_test")
-    files = glob.glob("test_migration/versions/*.py")
+        session.run("alembic", "revision", "-m", "migration_for_test")
+        files = glob.glob("test_migration/versions/*.py")
 
-    # updating the upgrade-script code
-    with open(files[0], "rb") as f:
-        script_code = f.read().decode()
+        # updating the upgrade-script code
+        with open(files[0], "rb") as f:
+            script_code = f.read().decode()
 
-    script_code = script_code.replace(
-        """def upgrade() -> None:\n    pass""", UPGRADE_CODE
-    )
-    with open(files[0], "wb") as f:
-        f.write(script_code.encode())
+        script_code = script_code.replace(
+            """def upgrade() -> None:\n    pass""", UPGRADE_CODE
+        )
+        with open(files[0], "wb") as f:
+            f.write(script_code.encode())
 
-    os.remove("test_migration/env.py")
-    shutil.copyfile("test_migration_env.py", "test_migration/env.py")
+        if os.path.exists("test_migration/env.py"):
+            os.remove("test_migration/env.py")
+        shutil.copyfile("test_migration_env.py", "test_migration/env.py")
 
-    # running the test migration
-    session.run("alembic", "upgrade", "head")
+        # running the test migration
+        session.run("alembic", "upgrade", "head")
 
-    # clearing the migration data
-    os.remove("alembic.ini")
-    shutil.rmtree("test_migration")
-    session.run("python", "migration_test_cleanup.py", db_url)
-    if os.path.exists(config_file) and config_file != "setup.cfg":
-        os.remove(config_file)
-    elif os.path.exists("test.cfg"):
-        os.remove("test.cfg")
+    finally:
+        # clearing the migration data
+        if os.path.exists("alembic.ini"):
+            os.remove("alembic.ini")
+        if os.path.exists("test_migration"):
+            shutil.rmtree("test_migration")
+
+        if os.path.exists(config_file):
+            session.run("python", "drop_test_database.py", success_codes=[0, 1])
 
 
 @nox.session(python=ALL_PYTHON)
@@ -419,8 +425,9 @@ def unit(session, test_type):
 def system(session, test_type):
     """Run SQLAlchemy dialect system test suite."""
 
-    config_file = f"test_{test_type}_{session.python}.cfg"
-    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_file
+    config_file = os.environ.setdefault(
+        "SQLALCHEMY_SPANNER_CONFIG", f"test_{test_type}_{session.python}.cfg"
+    )
 
     if not os.environ.get("GOOGLE_APPLICATION_CREDENTIALS", "") and not os.environ.get(
         "SPANNER_EMULATOR_HOST", ""

From 4324daf90c2188e12b5dcad46c1b6e21daee8d1b Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 07:22:38 -0400
Subject: [PATCH 15/21] fix(tests): eliminate race conditions in parallel
 database testing

---
 packages/sqlalchemy-spanner/create_test_database.py |  2 +-
 packages/sqlalchemy-spanner/noxfile.py              | 13 +++++++++----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 4fbb2851d808..33d838bce334 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -142,7 +142,7 @@ def create_test_instance():
     # Format: sp_test_{timestamp_in_seconds}_{rand_hex3} (compliant with Spanner naming: ^[a-z][a-z0-9_]{1,29}$)
     creation_timestamp = time.time()
     timestamp_part = str(int(creation_timestamp))
-    rand_part = uuid.uuid4().hex[:3]
+    rand_part = uuid.uuid4().hex[:8]
     database_id = f"sp_test_{timestamp_part}_{rand_part}"
 
     try:
diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index c385da703cd9..4681db029e19 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -21,6 +21,7 @@
 import pathlib
 import re
 import shutil
+import uuid
 
 import nox
 
@@ -180,7 +181,8 @@ def lint_setup_py(session):
 def compliance_test_14(session):
     """Run SQLAlchemy dialect compliance test suite."""
     config_file = os.environ.setdefault(
-        "SQLALCHEMY_SPANNER_CONFIG", f"test_compliance_14_{session.python}.cfg"
+        "SQLALCHEMY_SPANNER_CONFIG",
+        f"test_compliance_14_{session.python}_{uuid.uuid4().hex[:6]}.cfg",
     )
 
     # Check the value of `RUN_COMPLIANCE_TESTS` env var. It defaults to true.
@@ -233,7 +235,8 @@ def compliance_test_14(session):
 def compliance_test_20(session):
     """Run SQLAlchemy dialect compliance test suite."""
     config_file = os.environ.setdefault(
-        "SQLALCHEMY_SPANNER_CONFIG", f"test_compliance_20_{session.python}.cfg"
+        "SQLALCHEMY_SPANNER_CONFIG",
+        f"test_compliance_20_{session.python}_{uuid.uuid4().hex[:6]}.cfg",
     )
 
     # Check the value of `RUN_COMPLIANCE_TESTS` env var. It defaults to true.
@@ -327,7 +330,8 @@ def _migration_test(session):
     import shutil
 
     config_file = os.environ.setdefault(
-        "SQLALCHEMY_SPANNER_CONFIG", f"test_migration_{session.python}.cfg"
+        "SQLALCHEMY_SPANNER_CONFIG",
+        f"test_migration_{session.python}_{uuid.uuid4().hex[:6]}.cfg",
     )
 
     session.install(*MIGRATION_TEST_DEPENDENCIES)
@@ -426,7 +430,8 @@ def system(session, test_type):
     """Run SQLAlchemy dialect system test suite."""
 
     config_file = os.environ.setdefault(
-        "SQLALCHEMY_SPANNER_CONFIG", f"test_{test_type}_{session.python}.cfg"
+        "SQLALCHEMY_SPANNER_CONFIG",
+        f"test_{test_type}_{session.python}_{uuid.uuid4().hex[:6]}.cfg",
     )
 
     if not os.environ.get("GOOGLE_APPLICATION_CREDENTIALS", "") and not os.environ.get(

From 6221d4cfdacd1aa41cbf51ad06ec6d5b89a31ed8 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 07:35:21 -0400
Subject: [PATCH 16/21] chore(tests): remove obsolete migration_test_cleanup.py

---
 .../migration_test_cleanup.py                 | 40 -------------------
 1 file changed, 40 deletions(-)
 delete mode 100644 packages/sqlalchemy-spanner/migration_test_cleanup.py

diff --git a/packages/sqlalchemy-spanner/migration_test_cleanup.py b/packages/sqlalchemy-spanner/migration_test_cleanup.py
deleted file mode 100644
index b6efb15910e0..000000000000
--- a/packages/sqlalchemy-spanner/migration_test_cleanup.py
+++ /dev/null
@@ -1,40 +0,0 @@
-# -*- coding: utf-8 -*-
-#
-# Copyright 2021 Google LLC
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     https://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import re
-import sys
-
-from google.cloud import spanner
-
-
-def main(argv):
-    db_url = argv[0]
-
-    project = re.findall(r"projects(.*?)instances", db_url)
-    instance_id = re.findall(r"instances(.*?)databases", db_url)
-    database_id = re.findall(r"databases(.*?)$", db_url)
-
-    client = spanner.Client(project="".join(project).replace("/", ""))
-    instance = client.instance(instance_id="".join(instance_id).replace("/", ""))
-    database = instance.database("".join(database_id).replace("/", ""))
-
-    database.update_ddl(
-        ["DROP TABLE IF EXISTS account", "DROP TABLE IF EXISTS alembic_version"]
-    ).result(120)
-
-
-if __name__ == "__main__":
-    main(sys.argv[1:])

From 7bce8acae7945cf427eb45f9cf0b1b5efd8c43fc Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 08:08:17 -0400
Subject: [PATCH 17/21] fix(tests): use Spanner-specific fixture in SQLAlchemy
 1.4 NumericTest

---
 packages/sqlalchemy-spanner/tests/test_suite_14.py | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/packages/sqlalchemy-spanner/tests/test_suite_14.py b/packages/sqlalchemy-spanner/tests/test_suite_14.py
index 6494c414069a..9643f898e540 100644
--- a/packages/sqlalchemy-spanner/tests/test_suite_14.py
+++ b/packages/sqlalchemy-spanner/tests/test_suite_14.py
@@ -1576,7 +1576,7 @@ def run(type_, input_, output, filter_=None, check_scale=False):
         return run
 
     @emits_warning(r".*does \*not\* support Decimal objects natively")
-    def test_render_literal_numeric(self, literal_round_trip):
+    def test_render_literal_numeric(self, literal_round_trip_spanner):
         """
         SPANNER OVERRIDE:
 
@@ -1585,14 +1585,14 @@ def test_render_literal_numeric(self, literal_round_trip):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip(
+        literal_round_trip_spanner(
             Numeric(precision=8, scale=4),
             [decimal.Decimal("15.7563")],
             [decimal.Decimal("15.7563")],
         )
 
     @emits_warning(r".*does \*not\* support Decimal objects natively")
-    def test_render_literal_numeric_asfloat(self, literal_round_trip):
+    def test_render_literal_numeric_asfloat(self, literal_round_trip_spanner):
         """
         SPANNER OVERRIDE:
 
@@ -1601,13 +1601,13 @@ def test_render_literal_numeric_asfloat(self, literal_round_trip):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip(
+        literal_round_trip_spanner(
             Numeric(precision=8, scale=4, asdecimal=False),
             [decimal.Decimal("15.7563")],
             [15.7563],
         )
 
-    def test_render_literal_float(self, literal_round_trip):
+    def test_render_literal_float(self, literal_round_trip_spanner):
         """
         SPANNER OVERRIDE:
 
@@ -1616,7 +1616,7 @@ def test_render_literal_float(self, literal_round_trip):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip(
+        literal_round_trip_spanner(
             Float(4),
             [decimal.Decimal("15.7563")],
             [15.7563],

From 965ef97301ea7167cc8bb607f1c3e6ccb7933c07 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 09:41:50 -0400
Subject: [PATCH 18/21] fix(sqlalchemy-spanner): use literal_round_trip fixture
 to avoid literal_execute TypeError

---
 packages/sqlalchemy-spanner/tests/test_suite_14.py | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/packages/sqlalchemy-spanner/tests/test_suite_14.py b/packages/sqlalchemy-spanner/tests/test_suite_14.py
index 9643f898e540..6494c414069a 100644
--- a/packages/sqlalchemy-spanner/tests/test_suite_14.py
+++ b/packages/sqlalchemy-spanner/tests/test_suite_14.py
@@ -1576,7 +1576,7 @@ def run(type_, input_, output, filter_=None, check_scale=False):
         return run
 
     @emits_warning(r".*does \*not\* support Decimal objects natively")
-    def test_render_literal_numeric(self, literal_round_trip_spanner):
+    def test_render_literal_numeric(self, literal_round_trip):
         """
         SPANNER OVERRIDE:
 
@@ -1585,14 +1585,14 @@ def test_render_literal_numeric(self, literal_round_trip_spanner):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip_spanner(
+        literal_round_trip(
             Numeric(precision=8, scale=4),
             [decimal.Decimal("15.7563")],
             [decimal.Decimal("15.7563")],
         )
 
     @emits_warning(r".*does \*not\* support Decimal objects natively")
-    def test_render_literal_numeric_asfloat(self, literal_round_trip_spanner):
+    def test_render_literal_numeric_asfloat(self, literal_round_trip):
         """
         SPANNER OVERRIDE:
 
@@ -1601,13 +1601,13 @@ def test_render_literal_numeric_asfloat(self, literal_round_trip_spanner):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip_spanner(
+        literal_round_trip(
             Numeric(precision=8, scale=4, asdecimal=False),
             [decimal.Decimal("15.7563")],
             [15.7563],
         )
 
-    def test_render_literal_float(self, literal_round_trip_spanner):
+    def test_render_literal_float(self, literal_round_trip):
         """
         SPANNER OVERRIDE:
 
@@ -1616,7 +1616,7 @@ def test_render_literal_float(self, literal_round_trip_spanner):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip_spanner(
+        literal_round_trip(
             Float(4),
             [decimal.Decimal("15.7563")],
             [15.7563],

From f1b034ad60fd0c996aaa61aacaae35d32afd26f5 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 09:55:59 -0400
Subject: [PATCH 19/21] fix(sqlalchemy-spanner): use unique table name
 t_literal_round_trip_spanner without literal_execute

---
 packages/sqlalchemy-spanner/tests/conftest.py      |  5 +----
 packages/sqlalchemy-spanner/tests/test_suite_14.py | 12 ++++++------
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/packages/sqlalchemy-spanner/tests/conftest.py b/packages/sqlalchemy-spanner/tests/conftest.py
index b949e1a4c47e..ec16ad532dde 100644
--- a/packages/sqlalchemy-spanner/tests/conftest.py
+++ b/packages/sqlalchemy-spanner/tests/conftest.py
@@ -75,7 +75,7 @@ def run(
         t.create(connection)
 
         for value in input_:
-            ins = t.insert().values(x=literal(value, type_, literal_execute=True))
+            ins = t.insert().values(x=literal(value, type_))
             connection.execute(ins)
 
         if support_whereclause:
@@ -85,13 +85,11 @@ def run(
                     == literal(
                         compare,
                         type_,
-                        literal_execute=True,
                     ),
                     t.c.x
                     == literal(
                         input_[0],
                         type_,
-                        literal_execute=True,
                     ),
                 )
             else:
@@ -100,7 +98,6 @@ def run(
                     == literal(
                         compare if compare is not None else input_[0],
                         type_,
-                        literal_execute=True,
                     )
                 )
         else:
diff --git a/packages/sqlalchemy-spanner/tests/test_suite_14.py b/packages/sqlalchemy-spanner/tests/test_suite_14.py
index 6494c414069a..9643f898e540 100644
--- a/packages/sqlalchemy-spanner/tests/test_suite_14.py
+++ b/packages/sqlalchemy-spanner/tests/test_suite_14.py
@@ -1576,7 +1576,7 @@ def run(type_, input_, output, filter_=None, check_scale=False):
         return run
 
     @emits_warning(r".*does \*not\* support Decimal objects natively")
-    def test_render_literal_numeric(self, literal_round_trip):
+    def test_render_literal_numeric(self, literal_round_trip_spanner):
         """
         SPANNER OVERRIDE:
 
@@ -1585,14 +1585,14 @@ def test_render_literal_numeric(self, literal_round_trip):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip(
+        literal_round_trip_spanner(
             Numeric(precision=8, scale=4),
             [decimal.Decimal("15.7563")],
             [decimal.Decimal("15.7563")],
         )
 
     @emits_warning(r".*does \*not\* support Decimal objects natively")
-    def test_render_literal_numeric_asfloat(self, literal_round_trip):
+    def test_render_literal_numeric_asfloat(self, literal_round_trip_spanner):
         """
         SPANNER OVERRIDE:
 
@@ -1601,13 +1601,13 @@ def test_render_literal_numeric_asfloat(self, literal_round_trip):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip(
+        literal_round_trip_spanner(
             Numeric(precision=8, scale=4, asdecimal=False),
             [decimal.Decimal("15.7563")],
             [15.7563],
         )
 
-    def test_render_literal_float(self, literal_round_trip):
+    def test_render_literal_float(self, literal_round_trip_spanner):
         """
         SPANNER OVERRIDE:
 
@@ -1616,7 +1616,7 @@ def test_render_literal_float(self, literal_round_trip):
         following insertions will fail with `Row [] already exists".
         Overriding the test to avoid the same failure.
         """
-        literal_round_trip(
+        literal_round_trip_spanner(
             Float(4),
             [decimal.Decimal("15.7563")],
             [15.7563],

From ef4f8a343e5c2931bff5d95002877783449106f1 Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 10:21:11 -0400
Subject: [PATCH 20/21] fix(sqlalchemy-spanner): pass config filename
 explicitly as command line argument to create and drop database scripts

---
 .../create_test_database.py                   | 37 ++++++++++++++++++-
 .../sqlalchemy-spanner/drop_test_database.py  | 10 ++++-
 packages/sqlalchemy-spanner/noxfile.py        | 30 ++++++++++-----
 3 files changed, 65 insertions(+), 12 deletions(-)

diff --git a/packages/sqlalchemy-spanner/create_test_database.py b/packages/sqlalchemy-spanner/create_test_database.py
index 33d838bce334..4c004fb05c97 100644
--- a/packages/sqlalchemy-spanner/create_test_database.py
+++ b/packages/sqlalchemy-spanner/create_test_database.py
@@ -160,5 +160,38 @@ def create_test_instance():
         json.dump({"database_id": database_id, "creation_time": creation_timestamp}, f)
 
 
-delete_stale_test_databases()
-create_test_instance()
+def main(argv):
+    config_filename = argv[0] if argv else os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_filename
+
+    delete_stale_test_databases()
+    create_test_instance()
+
+    instance_id = "sqlalchemy-dialect-test"
+    instance = CLIENT.instance(instance_id)
+
+    # Generate a session-isolated unique database ID within Spanner 30-char limit
+    # Format: sp_test_{timestamp_in_seconds}_{rand_hex8} (compliant with Spanner naming: ^[a-z][a-z0-9_]{1,29}$)
+    creation_timestamp = time.time()
+    timestamp_part = str(int(creation_timestamp))
+    rand_part = uuid.uuid4().hex[:8]
+    database_id = f"sp_test_{timestamp_part}_{rand_part}"
+
+    try:
+        database = instance.database(database_id)
+        created_op = database.create()
+        created_op.result(1800)
+    except AlreadyExists:
+        pass  # database was already created
+
+    set_test_config(PROJECT, instance_id, database_id)
+
+    # Record metadata for duration tracking on teardown
+    meta_path = os.path.join(os.path.dirname(__file__), ".db_session_info.json")
+    with open(meta_path, "w") as f:
+        json.dump({"database_id": database_id, "creation_time": creation_timestamp}, f)
+
+
+if __name__ == "__main__":
+    import sys
+    main(sys.argv[1:])
diff --git a/packages/sqlalchemy-spanner/drop_test_database.py b/packages/sqlalchemy-spanner/drop_test_database.py
index aa27569a575c..c9cee6b06635 100644
--- a/packages/sqlalchemy-spanner/drop_test_database.py
+++ b/packages/sqlalchemy-spanner/drop_test_database.py
@@ -107,4 +107,12 @@ def delete_test_database():
             pass
 
 
-delete_test_database()
+def main(argv):
+    config_filename = argv[0] if argv else os.getenv("SQLALCHEMY_SPANNER_CONFIG", "test.cfg")
+    os.environ["SQLALCHEMY_SPANNER_CONFIG"] = config_filename
+    delete_test_database()
+
+
+if __name__ == "__main__":
+    import sys
+    main(sys.argv[1:])
diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index 4681db029e19..b1887b3ec082 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -205,7 +205,7 @@ def compliance_test_14(session):
             *SQLALCHEMY_14_DEPENDENCIES,
             "--force-reinstall",
         )
-        session.run("python", "create_test_database.py")
+        session.run("python", "create_test_database.py", config_file)
         config = configparser.ConfigParser()
         config.read(config_file)
         db_url = config.get("db", "default")
@@ -226,9 +226,13 @@ def compliance_test_14(session):
         )
     finally:
         if os.path.exists(config_file):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", config_file, success_codes=[0, 1]
+            )
         elif os.path.exists("test.cfg"):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", "test.cfg", success_codes=[0, 1]
+            )
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION_FOR_SQLALCHEMY_20)
@@ -254,7 +258,7 @@ def compliance_test_20(session):
     try:
         session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
         session.install("-e", ".", "--force-reinstall")
-        session.run("python", "create_test_database.py")
+        session.run("python", "create_test_database.py", config_file)
         config = configparser.ConfigParser()
         config.read(config_file)
         db_url = config.get("db", "default")
@@ -276,9 +280,13 @@ def compliance_test_20(session):
         )
     finally:
         if os.path.exists(config_file):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", config_file, success_codes=[0, 1]
+            )
         elif os.path.exists("test.cfg"):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", "test.cfg", success_codes=[0, 1]
+            )
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION_FOR_SQLALCHEMY_20)
@@ -468,7 +476,7 @@ def system(session, test_type):
             session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
             session.install(".[tracing]")
             session.install(*SYSTEM_TEST_EXTERNAL_DEPENDENCIES)
-            session.run("python", "create_test_database.py")
+            session.run("python", "create_test_database.py", config_file)
             config = configparser.ConfigParser()
             config.read(config_file)
             db_url = config.get("db", "default")
@@ -490,9 +498,13 @@ def system(session, test_type):
             _migration_test(session)
     finally:
         if os.path.exists(config_file):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", config_file, success_codes=[0, 1]
+            )
         elif os.path.exists("test.cfg"):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", "test.cfg", success_codes=[0, 1]
+            )
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)

From 9469195780e8bcbc26dfad4f963478f6dd89c01b Mon Sep 17 00:00:00 2001
From: chalmer lowe <chalmerlowe@google.com>
Date: Thu, 20 Aug 2026 10:36:41 -0400
Subject: [PATCH 21/21] fix(sqlalchemy-spanner): pass config_file explicitly in
 _migration_test session as well

---
 packages/sqlalchemy-spanner/noxfile.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/packages/sqlalchemy-spanner/noxfile.py b/packages/sqlalchemy-spanner/noxfile.py
index b1887b3ec082..a09b96f44052 100644
--- a/packages/sqlalchemy-spanner/noxfile.py
+++ b/packages/sqlalchemy-spanner/noxfile.py
@@ -346,7 +346,7 @@ def _migration_test(session):
     session.install(".")
 
     try:
-        session.run("python", "create_test_database.py")
+        session.run("python", "create_test_database.py", config_file)
 
         config = configparser.ConfigParser()
         if os.path.exists(config_file):
@@ -391,7 +391,9 @@ def _migration_test(session):
             shutil.rmtree("test_migration")
 
         if os.path.exists(config_file):
-            session.run("python", "drop_test_database.py", success_codes=[0, 1])
+            session.run(
+                "python", "drop_test_database.py", config_file, success_codes=[0, 1]
+            )
 
 
 @nox.session(python=ALL_PYTHON)