2019-01-17 14:23:12 +00:00
|
|
|
#include <Storages/MarkCache.h>
|
|
|
|
#include <Storages/MergeTree/MarkRange.h>
|
|
|
|
#include <Storages/MergeTree/MergeTreeData.h>
|
|
|
|
#include <Storages/MergeTree/MergeTreeRangeReader.h>
|
|
|
|
#include <Compression/CachedCompressedReadBuffer.h>
|
|
|
|
#include <Compression/CompressedReadBufferFromFile.h>
|
|
|
|
|
|
|
|
|
|
|
|
namespace DB
|
|
|
|
{
|
|
|
|
|
|
|
|
class MergeTreeReaderStream
|
|
|
|
{
|
|
|
|
public:
|
|
|
|
MergeTreeReaderStream(
|
|
|
|
const String &path_prefix_, const String &extension_, size_t marks_count_,
|
|
|
|
const MarkRanges &all_mark_ranges,
|
|
|
|
MarkCache *mark_cache, bool save_marks_in_cache,
|
|
|
|
UncompressedCache *uncompressed_cache,
|
|
|
|
size_t aio_threshold, size_t max_read_buffer_size,
|
|
|
|
const ReadBufferFromFileBase::ProfileCallback &profile_callback, clockid_t clock_type);
|
|
|
|
|
|
|
|
void seekToMark(size_t index);
|
|
|
|
|
|
|
|
void seekToStart();
|
|
|
|
|
|
|
|
ReadBuffer *data_buffer;
|
|
|
|
|
|
|
|
private:
|
|
|
|
MergeTreeReaderStream() = default;
|
|
|
|
|
|
|
|
/// NOTE: lazily loads marks from the marks cache.
|
|
|
|
const MarkInCompressedFile &getMark(size_t index);
|
|
|
|
|
|
|
|
void loadMarks();
|
|
|
|
|
|
|
|
std::string path_prefix;
|
|
|
|
std::string extension;
|
|
|
|
|
|
|
|
size_t marks_count;
|
|
|
|
|
|
|
|
MarkCache *mark_cache;
|
|
|
|
bool save_marks_in_cache;
|
|
|
|
MarkCache::MappedPtr marks;
|
|
|
|
|
|
|
|
std::unique_ptr<CachedCompressedReadBuffer> cached_buffer;
|
|
|
|
std::unique_ptr<CompressedReadBufferFromFile> non_cached_buffer;
|
|
|
|
};
|
2019-01-29 20:00:12 +00:00
|
|
|
}
|