diff --git a/workspace-server/internal/registry/access_test.go b/workspace-server/internal/registry/access_test.go
index 537a0b62..54ad34e5 100644
--- a/workspace-server/internal/registry/access_test.go
+++ b/workspace-server/internal/registry/access_test.go
@@ -14,8 +14,9 @@ func setupMockDB(t *testing.T) sqlmock.Sqlmock {
 	if err != nil {
 		t.Fatalf("sqlmock: %v", err)
 	}
+	prevDB := db.DB
 	db.DB = mockDB
-	t.Cleanup(func() { mockDB.Close() })
+	t.Cleanup(func() { mockDB.Close(); db.DB = prevDB })
 	return mock
 }
 
diff --git a/workspace-server/internal/registry/healthsweep_test.go b/workspace-server/internal/registry/healthsweep_test.go
index ce82e027..45718cb9 100644
--- a/workspace-server/internal/registry/healthsweep_test.go
+++ b/workspace-server/internal/registry/healthsweep_test.go
@@ -31,8 +31,9 @@ func setupTestDB(t *testing.T) sqlmock.Sqlmock {
 	if err != nil {
 		t.Fatalf("failed to create sqlmock: %v", err)
 	}
+	prevDB := db.DB
 	db.DB = mockDB
-	t.Cleanup(func() { mockDB.Close() })
+	t.Cleanup(func() { mockDB.Close(); db.DB = prevDB })
 	return mock
 }
 
diff --git a/workspace-server/internal/registry/hibernation_test.go b/workspace-server/internal/registry/hibernation_test.go
index 76d6555f..f51226de 100644
--- a/workspace-server/internal/registry/hibernation_test.go
+++ b/workspace-server/internal/registry/hibernation_test.go
@@ -17,8 +17,9 @@ func setupHibernationMock(t *testing.T) sqlmock.Sqlmock {
 	if err != nil {
 		t.Fatalf("sqlmock.New: %v", err)
 	}
+	prevDB := db.DB
 	db.DB = mockDB
-	t.Cleanup(func() { mockDB.Close() })
+	t.Cleanup(func() { mockDB.Close(); db.DB = prevDB })
 	return mock
 }
 
diff --git a/workspace-server/internal/registry/liveness_test.go b/workspace-server/internal/registry/liveness_test.go
index d53fc007..6449b665 100644
--- a/workspace-server/internal/registry/liveness_test.go
+++ b/workspace-server/internal/registry/liveness_test.go
@@ -18,8 +18,9 @@ func setupLivenessTestDB(t *testing.T) sqlmock.Sqlmock {
 	if err != nil {
 		t.Fatalf("failed to create sqlmock: %v", err)
 	}
+	prevDB := db.DB
 	db.DB = mockDB
-	t.Cleanup(func() { mockDB.Close() })
+	t.Cleanup(func() { mockDB.Close(); db.DB = prevDB })
 	return mock
 }
 
diff --git a/workspace-server/internal/scheduler/scheduler_test.go b/workspace-server/internal/scheduler/scheduler_test.go
index 742ec0ad..aaa43369 100644
--- a/workspace-server/internal/scheduler/scheduler_test.go
+++ b/workspace-server/internal/scheduler/scheduler_test.go
@@ -24,8 +24,9 @@ func setupTestDB(t *testing.T) sqlmock.Sqlmock {
 	if err != nil {
 		t.Fatalf("failed to create sqlmock: %v", err)
 	}
+	prevDB := db.DB
 	db.DB = mockDB
-	t.Cleanup(func() { mockDB.Close() })
+	t.Cleanup(func() { mockDB.Close(); db.DB = prevDB })
 	return mock
 }