mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-10-09 18:10:48 +00:00
82 lines
2.4 KiB
C++
82 lines
2.4 KiB
C++
#pragma once
|
|
#include <DataStreams/IBlockInputStream.h>
|
|
#include <Storages/MergeTree/MergeTreeThreadSelectBlockInputStream.h>
|
|
#include <Storages/MergeTree/MergeTreeData.h>
|
|
#include <Storages/MergeTree/MarkRange.h>
|
|
#include <Storages/MergeTree/MergeTreeBlockReadUtils.h>
|
|
#include <Storages/SelectQueryInfo.h>
|
|
|
|
namespace DB
|
|
{
|
|
|
|
|
|
/// Used to read data from single part with select query
|
|
/// Cares about PREWHERE, virtual columns, indexes etc.
|
|
/// To read data from multiple parts, Storage (MergeTree) creates multiple such objects.
|
|
class MergeTreeReverseSelectBlockInputStream : public MergeTreeBaseSelectBlockInputStream
|
|
{
|
|
public:
|
|
MergeTreeReverseSelectBlockInputStream(
|
|
const MergeTreeData & storage,
|
|
const MergeTreeData::DataPartPtr & owned_data_part,
|
|
UInt64 max_block_size_rows,
|
|
size_t preferred_block_size_bytes,
|
|
size_t preferred_max_column_in_block_size_bytes,
|
|
Names column_names,
|
|
const MarkRanges & mark_ranges,
|
|
bool use_uncompressed_cache,
|
|
const PrewhereInfoPtr & prewhere_info,
|
|
bool check_columns,
|
|
size_t min_bytes_to_use_direct_io,
|
|
size_t max_read_buffer_size,
|
|
bool save_marks_in_cache,
|
|
const Names & virt_column_names = {},
|
|
size_t part_index_in_query = 0,
|
|
bool quiet = false);
|
|
|
|
~MergeTreeReverseSelectBlockInputStream() override;
|
|
|
|
String getName() const override { return "MergeTreeReverse"; }
|
|
|
|
Block getHeader() const override;
|
|
|
|
/// Closes readers and unlock part locks
|
|
void finish();
|
|
|
|
protected:
|
|
|
|
bool getNewTask() override;
|
|
Block readFromPart() override;
|
|
|
|
private:
|
|
Block header;
|
|
|
|
/// Used by Task
|
|
Names required_columns;
|
|
/// Names from header. Used in order to order columns in read blocks.
|
|
Names ordered_names;
|
|
NameSet column_name_set;
|
|
|
|
MergeTreeReadTaskColumns task_columns;
|
|
|
|
/// Data part will not be removed if the pointer owns it
|
|
MergeTreeData::DataPartPtr data_part;
|
|
/// Forbids to change columns list of the part during reading
|
|
std::shared_lock<std::shared_mutex> part_columns_lock;
|
|
|
|
/// Mark ranges we should read (in ascending order)
|
|
MarkRanges all_mark_ranges;
|
|
/// Total number of marks we should read
|
|
size_t total_marks_count = 0;
|
|
/// Value of _part_index virtual column (used only in SelectExecutor)
|
|
size_t part_index_in_query = 0;
|
|
|
|
String path;
|
|
|
|
Blocks blocks;
|
|
|
|
Logger * log = &Logger::get("MergeTreeReverseSelectBlockInputStream");
|
|
};
|
|
|
|
}
|