diff --git a/bigquery/biglake/bigquery_query_manifest_external_table_test.py b/bigquery/biglake/bigquery_query_manifest_external_table_test.py
index cfe10fcdfa..b6f06dc9c0 100644
--- a/bigquery/biglake/bigquery_query_manifest_external_table_test.py
+++ b/bigquery/biglake/bigquery_query_manifest_external_table_test.py
@@ -26,7 +26,6 @@ def test_query_manifest_external_table_success(
     mock_client = mock.MagicMock()
     mock_job = mock.MagicMock()
     mock_job.job_id = "example-job-123"
-    mock_job.statement_type = "SCRIPT"
     mock_row = mock.MagicMock()
     mock_job.result.return_value = [mock_row]
     mock_client.query.return_value = mock_job
@@ -54,7 +53,9 @@ def test_query_manifest_external_table_error(
     capsys: pytest.CaptureFixture[str],
 ) -> None:
     mock_client = mock.MagicMock()
-    mock_client.query.side_effect = exceptions.NotFound("resource error")
+    mock_job = mock.MagicMock()
+    mock_job.result.side_effect = exceptions.NotFound("resource error")
+    mock_client.query.return_value = mock_job
     monkeypatch.setattr(
         bigquery_query_manifest_external_table.bigquery,
         "Client",
diff --git a/bigquery/search/bigquery_create_search_index.py b/bigquery/search/bigquery_create_search_index.py
index 6aeff84cc6..ff690d0019 100644
--- a/bigquery/search/bigquery_create_search_index.py
+++ b/bigquery/search/bigquery_create_search_index.py
@@ -38,7 +38,7 @@ def create_search_index(
     table_ref = f"{project_id}.{dataset_id}.{table_id}"
     # Indexing ALL COLUMNS enables full-text SEARCH queries across every STRING or JSON field.
     sql = f"""
-        CREATE SEARCH INDEX `{index_name}`
+        CREATE SEARCH INDEX IF NOT EXISTS `{index_name}`
         ON `{table_ref}`(ALL COLUMNS);
     """
 
@@ -46,10 +46,10 @@ def create_search_index(
         print(f"Creating search index {index_name} on table: {table_ref}")
         query_job = client.query(sql)
         query_job.result()
-    except exceptions.AlreadyExists as err:
+    except exceptions.NotFound as err:
         print(
-            f"error: search index '{index_name}' already exists on table "
-            f"'{table_id}' in dataset '{dataset_id}' for project '{project_id}': {err.message}",
+            f"error: table '{table_id}' or dataset '{dataset_id}' not found "
+            f"for project '{project_id}': {err.message}",
             file=sys.stderr,
         )
         return
diff --git a/bigquery/search/bigquery_create_search_index_test.py b/bigquery/search/bigquery_create_search_index_test.py
index f1a77df6bb..48242a0501 100644
--- a/bigquery/search/bigquery_create_search_index_test.py
+++ b/bigquery/search/bigquery_create_search_index_test.py
@@ -27,8 +27,7 @@ def test_create_search_index_success(
     mock_job = mock.MagicMock()
     mock_job.job_id = "example-job-123"
     mock_job.statement_type = "SCRIPT"
-    mock_row = mock.MagicMock()
-    mock_job.result.return_value = [mock_row]
+    mock_job.result.return_value = []
     mock_client.query.return_value = mock_job
     monkeypatch.setattr(
         bigquery_create_search_index.bigquery,
@@ -53,7 +52,9 @@ def test_create_search_index_error(
     capsys: pytest.CaptureFixture[str],
 ) -> None:
     mock_client = mock.MagicMock()
-    mock_client.query.side_effect = exceptions.AlreadyExists("resource error")
+    mock_job = mock.MagicMock()
+    mock_job.result.side_effect = exceptions.NotFound("resource error")
+    mock_client.query.return_value = mock_job
     monkeypatch.setattr(
         bigquery_create_search_index.bigquery,
         "Client",
diff --git a/bigquery/vector_search/bigquery_drop_vector_index.py b/bigquery/vector_search/bigquery_drop_vector_index.py
index 91c9c45e94..974d712e97 100644
--- a/bigquery/vector_search/bigquery_drop_vector_index.py
+++ b/bigquery/vector_search/bigquery_drop_vector_index.py
@@ -45,8 +45,8 @@ def drop_vector_index(
         query_job.result()
     except exceptions.NotFound as err:
         print(
-            f"error: table '{table_id}' or vector index '{index_name}' not found in "
-            f"dataset '{dataset_id}' for project '{project_id}': {err.message}",
+            f"error: table '{table_id}' or dataset '{dataset_id}' not found in "
+            f"project '{project_id}': {err.message}",
             file=sys.stderr,
         )
         return
diff --git a/bigquery/vector_search/bigquery_drop_vector_index_test.py b/bigquery/vector_search/bigquery_drop_vector_index_test.py
index bf64f1f808..f441584f66 100644
--- a/bigquery/vector_search/bigquery_drop_vector_index_test.py
+++ b/bigquery/vector_search/bigquery_drop_vector_index_test.py
@@ -27,8 +27,7 @@ def test_drop_vector_index_success(
     mock_job = mock.MagicMock()
     mock_job.job_id = "example-job-123"
     mock_job.statement_type = "SCRIPT"
-    mock_row = mock.MagicMock()
-    mock_job.result.return_value = [mock_row]
+    mock_job.result.return_value = []
     mock_client.query.return_value = mock_job
     monkeypatch.setattr(
         bigquery_drop_vector_index.bigquery,
@@ -53,7 +52,9 @@ def test_drop_vector_index_error(
     capsys: pytest.CaptureFixture[str],
 ) -> None:
     mock_client = mock.MagicMock()
-    mock_client.query.side_effect = exceptions.NotFound("resource error")
+    mock_job = mock.MagicMock()
+    mock_job.result.side_effect = exceptions.NotFound("resource error")
+    mock_client.query.return_value = mock_job
     monkeypatch.setattr(
         bigquery_drop_vector_index.bigquery,
         "Client",