Method buildQueryPipeline

src/QueryPlan/QueryPlan.cpp:269–340

}

QueryPipelinePtr QueryPlan::buildQueryPipeline(
    const QueryPlanOptimizationSettings & optimization_settings, const BuildQueryPipelineSettings & build_pipeline_settings)
{
    checkInitialized();

    if (!optimization_settings.enable_optimizer)
    {
        optimize(optimization_settings);
    }

    struct Frame
    {
        Node * node = {};
        QueryPipelines pipelines = {};
    };

    QueryPipelinePtr last_pipeline;

    std::stack<Frame> stack;
    stack.push(Frame{.node = root});
    Stopwatch watch;
    while (!stack.empty())
    {
        auto & frame = stack.top();

        if (last_pipeline)
        {
            frame.pipelines.emplace_back(std::move(last_pipeline));
            last_pipeline = nullptr; //-V1048
        }

        size_t next_child = frame.pipelines.size();
        if (next_child == frame.node->children.size())
        {
            bool limit_max_threads = frame.pipelines.empty();
            try
            {
                last_pipeline = frame.node->step->updatePipeline(std::move(frame.pipelines), build_pipeline_settings);
                updatePipelineStepInfo(last_pipeline, frame.node->step, frame.node->id);
            }
            catch (const Exception & e) /// Typical for an incorrect username, password, or address.
            {
                LOG_ERROR(log, "Build pipeline error {}", e.what());
                throw;
            }
            // #ifndef NDEBUG
            //             if (optimization_settings.enable_optimizer)
            //             {
            //                 const auto & output_header = frame.node->step->getOutputStream().header;
            //                 const auto & pipeline_header = last_pipeline->getHeader();
            //                 assertBlocksHaveEqualStructure(
            //                     output_header,
            //                     pipeline_header,
            //                     "QueryPlan::buildQueryPipeline for " + frame.node->step->getName() + " (output header, pipeline header)");
            //             }
            // #endif

            if (limit_max_threads && max_threads)