ClickHouse/dbms/src/Storages/StorageStripeLog.h
2019-08-29 19:17:47 +03:00

84 lines
2.3 KiB
C++

#pragma once
#include <map>
#include <shared_mutex>
#include <ext/shared_ptr_helper.h>
#include <Poco/File.h>
#include <Storages/IStorage.h>
#include <Common/FileChecker.h>
#include <Common/escapeForFileName.h>
#include <Core/Defines.h>
namespace DB
{
/** Implements a table engine that is suitable for small chunks of the log.
* In doing so, stores all the columns in a single Native file, with a nearby index.
*/
class StorageStripeLog : public ext::shared_ptr_helper<StorageStripeLog>, public IStorage
{
friend class StripeLogBlockInputStream;
friend class StripeLogBlockOutputStream;
friend struct ext::shared_ptr_helper<StorageStripeLog>;
public:
std::string getName() const override { return "StripeLog"; }
std::string getTableName() const override { return table_name; }
std::string getDatabaseName() const override { return database_name; }
BlockInputStreams read(
const Names & column_names,
const SelectQueryInfo & query_info,
const Context & context,
QueryProcessingStage::Enum processed_stage,
size_t max_block_size,
unsigned num_streams) override;
BlockOutputStreamPtr write(const ASTPtr & query, const Context & context) override;
void rename(const String & new_path_to_db, const String & new_database_name, const String & new_table_name, TableStructureWriteLockHolder &) override;
CheckResults checkData(const ASTPtr & /* query */, const Context & /* context */) override;
/// Data of the file.
struct ColumnData
{
Poco::File data_file;
};
using Files_t = std::map<String, ColumnData>;
std::string full_path() const { return path + escapeForFileName(table_name) + '/';}
Strings getDataPaths() const override { return {full_path()}; }
void truncate(const ASTPtr &, const Context &, TableStructureWriteLockHolder &) override;
private:
String path;
String table_name;
String database_name;
size_t max_compress_block_size;
FileChecker file_checker;
mutable std::shared_mutex rwlock;
Logger * log;
protected:
StorageStripeLog(
const std::string & path_,
const std::string & database_name_,
const std::string & table_name_,
const ColumnsDescription & columns_,
const ConstraintsDescription & constraints_,
bool attach,
size_t max_compress_block_size_);
};
}