ClickHouse/dbms/include/DB/Storages/StorageSystemNumbers.h

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#pragma once
#include <Poco/SharedPtr.h>
#include <DB/Storages/IStorage.h>
namespace DB
{
using Poco::SharedPtr;
/** Реализует хранилище для системной таблицы Numbers.
* Таблица содержит единственный столбец number UInt64.
* Из этой таблицы можно прочитать все натуральные числа, начиная с 0 (до 2^64 - 1, а потом заново).
*/
class StorageSystemNumbers : public IStorage
{
public:
static StoragePtr create(const std::string & name_, bool multithreaded_ = false);
std::string getName() const override { return "SystemNumbers"; }
std::string getTableName() const override { return name; }
const NamesAndTypesList & getColumnsList() const override { return columns; }
BlockInputStreams read(
const Names & column_names,
ASTPtr query,
const Settings & settings,
QueryProcessingStage::Enum & processed_stage,
size_t max_block_size = DEFAULT_BLOCK_SIZE,
unsigned threads = 1) override;
private:
const std::string name;
NamesAndTypesList columns;
bool multithreaded;
StorageSystemNumbers(const std::string & name_, bool multithreaded_);
};
}