If they are defined, they can override table-level settings.
ContextPtr query_context, const StorageSnapshotPtr & storage_snapshot, SelectQueryInfo & query_info) const
{
    const auto & metadata_snapshot = storage_snapshot->metadata;
    const auto & settings = query_context->getSettingsRef();
    if (!settings.allow_experimental_projection_optimization || query_info.ignore_projections || query_info.is_projection_query)
        return std::nullopt;
    /
    if (settings.parallel_replicas_count > 1 || settings.max_parallel_replicas > 1)
        return std::nullopt;
    auto query_ptr = query_info.original_query;
    auto * select_query = query_ptr->as<ASTSelectQuery>();
    if (!select_query)
        return std::nullopt;
    /
    if (select_query->final())
        return std::nullopt;
    /
    if (select_query->sampleSize())