contrib/clickhouse/src/Processors/QueryPlan/OffsetStep.h


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#pragma once
#include <Processors/QueryPlan/ITransformingStep.h>
#include <QueryPipeline/SizeLimits.h>

namespace DB
{

/// Executes OFFSET (without LIMIT). See OffsetTransform.
class OffsetStep : public ITransformingStep
{
public:
    OffsetStep(const DataStream & input_stream_, size_t offset_);

    String getName() const override { return "Offset"; }

    void transformPipeline(QueryPipelineBuilder & pipeline, const BuildQueryPipelineSettings &) override;

    void describeActions(JSONBuilder::JSONMap & map) const override;
    void describeActions(FormatSettings & settings) const override;

private:
    void updateOutputStream() override
    {
        output_stream = createOutputStream(input_streams.front(), input_streams.front().header, getDataStreamTraits());
    }

    size_t offset;
};

}