public void testDeleteByQuery() {
        // Create test data
        client.prepareIndex().setIndex(TEST_INDEX).setId("1").setSource("field", "value1").execute().actionGet();
        client.prepareIndex().setIndex(TEST_INDEX).setId("2").setSource("field", "value2").execute().actionGet();
        client.admin().indices().prepareRefresh(TEST_INDEX).execute().actionGet();

        // Delete by query

        try {
            // This will likely fail due to missing SearchEngineClient setup,
            // but we can verify the method signature and basic functionality
            SearchEngineUtil.scroll("test_index", hit -> {
                callbackCount.incrementAndGet();
                return true; // Continue processing
            });
        } catch (Exception e) {