mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-10-01 06:00:49 +00:00
124 lines
2.9 KiB
C++
124 lines
2.9 KiB
C++
#include <Processors/Transforms/ExtremesTransform.h>
|
|
|
|
#include <Core/Field.h>
|
|
|
|
namespace DB
|
|
{
|
|
|
|
ExtremesTransform::ExtremesTransform(const Block & header)
|
|
: ISimpleTransform(header, header, true)
|
|
{
|
|
/// Port for Extremes.
|
|
outputs.emplace_back(outputs.front().getHeader(), this);
|
|
}
|
|
|
|
IProcessor::Status ExtremesTransform::prepare()
|
|
{
|
|
if (!finished_transform)
|
|
{
|
|
auto status = ISimpleTransform::prepare();
|
|
|
|
if (status != Status::Finished)
|
|
return status;
|
|
|
|
finished_transform = true;
|
|
}
|
|
|
|
auto & totals_output = getExtremesPort();
|
|
|
|
/// Check can output.
|
|
if (totals_output.isFinished())
|
|
return Status::Finished;
|
|
|
|
if (!totals_output.canPush())
|
|
return Status::PortFull;
|
|
|
|
if (!extremes && !extremes_columns.empty())
|
|
return Status::Ready;
|
|
|
|
if (extremes)
|
|
totals_output.push(std::move(extremes));
|
|
|
|
totals_output.finish();
|
|
return Status::Finished;
|
|
}
|
|
|
|
void ExtremesTransform::work()
|
|
{
|
|
if (finished_transform)
|
|
{
|
|
if (!extremes && !extremes_columns.empty())
|
|
extremes.setColumns(std::move(extremes_columns), 2);
|
|
}
|
|
else
|
|
ISimpleTransform::work();
|
|
}
|
|
|
|
void ExtremesTransform::transform(DB::Chunk & chunk)
|
|
{
|
|
|
|
if (chunk.getNumRows() == 0)
|
|
return;
|
|
|
|
size_t num_columns = chunk.getNumColumns();
|
|
const auto & columns = chunk.getColumns();
|
|
|
|
if (extremes_columns.empty())
|
|
{
|
|
extremes_columns.resize(num_columns);
|
|
|
|
for (size_t i = 0; i < num_columns; ++i)
|
|
{
|
|
const ColumnPtr & src = columns[i];
|
|
|
|
if (isColumnConst(*src))
|
|
{
|
|
/// Equal min and max.
|
|
extremes_columns[i] = src->cloneResized(2);
|
|
}
|
|
else
|
|
{
|
|
Field min_value;
|
|
Field max_value;
|
|
|
|
src->getExtremes(min_value, max_value);
|
|
|
|
extremes_columns[i] = src->cloneEmpty();
|
|
|
|
extremes_columns[i]->insert(min_value);
|
|
extremes_columns[i]->insert(max_value);
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for (size_t i = 0; i < num_columns; ++i)
|
|
{
|
|
if (isColumnConst(*extremes_columns[i]))
|
|
continue;
|
|
|
|
Field min_value = (*extremes_columns[i])[0];
|
|
Field max_value = (*extremes_columns[i])[1];
|
|
|
|
Field cur_min_value;
|
|
Field cur_max_value;
|
|
|
|
columns[i]->getExtremes(cur_min_value, cur_max_value);
|
|
|
|
if (cur_min_value < min_value)
|
|
min_value = cur_min_value;
|
|
if (cur_max_value > max_value)
|
|
max_value = cur_max_value;
|
|
|
|
MutableColumnPtr new_extremes = extremes_columns[i]->cloneEmpty();
|
|
|
|
new_extremes->insert(min_value);
|
|
new_extremes->insert(max_value);
|
|
|
|
extremes_columns[i] = std::move(new_extremes);
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|