ClickHouse/src/Databases/DatabasesCommon.h
2022-06-30 08:37:17 +02:00

58 lines
2.3 KiB
C++

#pragma once
#include <base/types.h>
#include <Parsers/IAST.h>
#include <Storages/IStorage_fwd.h>
#include <Databases/IDatabase.h>
#include <mutex>
/// General functionality for several different database engines.
namespace DB
{
void applyMetadataChangesToCreateQuery(const ASTPtr & query, const StorageInMemoryMetadata & metadata);
ASTPtr getCreateQueryFromStorage(const StoragePtr & storage, const ASTPtr & ast_storage, bool only_ordinary, uint32_t max_parser_depth, bool throw_on_error);
/// Cleans a CREATE QUERY from temporary flags like "IF NOT EXISTS", "OR REPLACE", "AS SELECT" (for non-views), etc.
void cleanupObjectDefinitionFromTemporaryFlags(ASTCreateQuery & query);
class Context;
/// A base class for databases that manage their own list of tables.
class DatabaseWithOwnTablesBase : public IDatabase, protected WithContext
{
public:
bool isTableExist(const String & table_name, ContextPtr context) const override;
StoragePtr tryGetTable(const String & table_name, ContextPtr context) const override;
bool empty() const override;
void attachTable(ContextPtr context, const String & table_name, const StoragePtr & table, const String & relative_table_path) override;
StoragePtr detachTable(ContextPtr context, const String & table_name) override;
DatabaseTablesIteratorPtr getTablesIterator(ContextPtr context, const FilterByNameFunction & filter_by_table_name) const override;
std::vector<std::pair<ASTPtr, StoragePtr>> getTablesForBackup(const FilterByNameFunction & filter, const ContextPtr & local_context) const override;
void createTableRestoredFromBackup(const ASTPtr & create_table_query, ContextMutablePtr local_context, std::shared_ptr<IRestoreCoordination> restore_coordination, UInt64 timeout_ms) override;
void shutdown() override;
~DatabaseWithOwnTablesBase() override;
protected:
Tables tables TSA_GUARDED_BY(mutex);
Poco::Logger * log;
DatabaseWithOwnTablesBase(const String & name_, const String & logger, ContextPtr context);
void attachTableUnlocked(const String & table_name, const StoragePtr & table) TSA_REQUIRES(mutex);
StoragePtr detachTableUnlocked(const String & table_name) TSA_REQUIRES(mutex);
StoragePtr getTableUnlocked(const String & table_name) const TSA_REQUIRES(mutex);
};
}