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

42 lines
979 B
C
Raw Normal View History

2012-06-18 07:49:19 +00:00
#pragma once
#include <Poco/SharedPtr.h>
#include <DB/Storages/IStorage.h>
#include <DB/DataStreams/IProfilingBlockInputStream.h>
#include <DB/Interpreters/Context.h>
namespace DB
{
using Poco::SharedPtr;
/** Реализует системную таблицу databases, которая позволяет получить информацию о всех БД.
*/
class StorageSystemDatabases : public IStorage
{
public:
StorageSystemDatabases(const std::string & name_, const Context & context_);
std::string getName() const { return "SystemDatabases"; }
std::string getTableName() const { return name; }
const NamesAndTypesList & getColumnsList() const { return columns; }
BlockInputStreams read(
const Names & column_names,
ASTPtr query,
QueryProcessingStage::Enum & processed_stage,
size_t max_block_size = DEFAULT_BLOCK_SIZE,
unsigned threads = 1);
private:
const std::string name;
const Context & context;
NamesAndTypesList columns;
};
}