ClickHouse/dbms/Storages/System/StorageSystemOne.cpp
Ivan 97f2a2213e
Move all folders inside /dbms one level up (#9974)
* Move some code outside dbms/src folder
* Fix paths
2020-04-02 02:51:21 +03:00

47 lines
1.1 KiB
C++

#include <Common/Exception.h>
#include <Columns/ColumnsNumber.h>
#include <DataTypes/DataTypesNumber.h>
#include <Storages/System/StorageSystemOne.h>
#include <Processors/Sources/SourceFromSingleChunk.h>
#include <Processors/Pipe.h>
namespace DB
{
StorageSystemOne::StorageSystemOne(const std::string & name_)
: IStorage({"system", name_})
{
setColumns(ColumnsDescription({{"dummy", std::make_shared<DataTypeUInt8>()}}));
}
Pipes 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);
Block header{ColumnWithTypeAndName(
DataTypeUInt8().createColumn(),
std::make_shared<DataTypeUInt8>(),
"dummy")};
auto column = DataTypeUInt8().createColumnConst(1, 0u)->convertToFullColumnIfConst();
Chunk chunk({ std::move(column) }, 1);
Pipes pipes;
pipes.emplace_back(std::make_shared<SourceFromSingleChunk>(std::move(header), std::move(chunk)));
return pipes;
}
}