ClickHouse/dbms/src/Storages/System/StorageSystemOne.cpp

39 lines
951 B
C++

#include <Common/Exception.h>
#include <Columns/ColumnsNumber.h>
#include <DataTypes/DataTypesNumber.h>
#include <DataStreams/OneBlockInputStream.h>
#include <Storages/System/StorageSystemOne.h>
namespace DB
{
StorageSystemOne::StorageSystemOne(const std::string & name_)
: name(name_)
{
setColumns(ColumnsDescription({{"dummy", std::make_shared<DataTypeUInt8>()}}));
}
BlockInputStreams StorageSystemOne::read(
const Names & column_names,
const SelectQueryInfo &,
const Context & /*context*/,
QueryProcessingStage::Enum /*processed_stage*/,
const size_t /*max_block_size*/,
const unsigned /*num_streams*/)
{
check(column_names);
return BlockInputStreams(1, std::make_shared<OneBlockInputStream>(
Block{ColumnWithTypeAndName(
DataTypeUInt8().createColumnConst(1, UInt64(0))->convertToFullColumnIfConst(),
std::make_shared<DataTypeUInt8>(),
"dummy")}));
}
}