message: [Ready to merge] Fix access violation issue that can appear if configuring no volatile_db .
diff: @@ -352,15 +352,16 @@ void parameter_server<TypeHashKey>::update_database_per_model(
  const std::string tag_name = make_tag_name(
  inference_params.model_name, ps_config_.emb_table_name_[inference_params.model_name][j]);
  +
  + // Populate volatile database(s).
  + if (volatile_db_) {
  const size_t volatile_capacity = volatile_db_->capacity(tag_name);
  const size_t volatile_cache_amount =
  (num_key <= volatile_capacity)
  ? num_key
  - : static_cast<size_t>(volatile_db_cache_rate_ * static_cast<double>(volatile_capacity) +
  - 0.5);
  + : static_cast<size_t>(
  + volatile_db_cache_rate_ * static_cast<double>(volatile_capacity) + 0.5);
  - // Populate volatile database(s).
  - if (volatile_db_) {
  HCTR_CHECK(volatile_db_->insert(tag_name, volatile_cache_amount, key_vec.data(),
  reinterpret_cast<const char*>(vec_vec.data()),
  embedding_size * sizeof(float)));
  