ClickHouse/src/Databases/DatabaseOnDisk.h
2021-08-23 23:41:45 +03:00

103 lines
3.8 KiB
C++

#pragma once
#include <Common/escapeForFileName.h>
#include <Common/quoteString.h>
#include <Databases/DatabasesCommon.h>
#include <Parsers/ASTCreateQuery.h>
#include <Storages/IStorage.h>
namespace DB
{
class Context;
std::pair<String, StoragePtr> createTableFromAST(
ASTCreateQuery ast_create_query,
const String & database_name,
const String & table_data_path_relative,
ContextMutablePtr context,
bool has_force_restore_data_flag);
/** Get the string with the table definition based on the CREATE query.
* It is an ATTACH query that you can execute to create a table from the correspondent database.
* See the implementation.
*/
String getObjectDefinitionFromCreateQuery(const ASTPtr & query);
void applyMetadataChangesToCreateQuery(const ASTPtr & query, const StorageInMemoryMetadata & metadata);
/* Class to provide basic operations with tables when metadata is stored on disk in .sql files.
*/
class DatabaseOnDisk : public DatabaseWithOwnTablesBase
{
public:
DatabaseOnDisk(const String & name, const String & metadata_path_, const String & data_path_, const String & logger, ContextPtr context);
void createTable(
ContextPtr context,
const String & table_name,
const StoragePtr & table,
const ASTPtr & query) override;
void detachTablePermanently(ContextPtr context, const String & table_name) override;
void dropTable(
ContextPtr context,
const String & table_name,
bool no_delay) override;
void renameTable(
ContextPtr context,
const String & table_name,
IDatabase & to_database,
const String & to_table_name,
bool exchange,
bool dictionary) override;
ASTPtr getCreateDatabaseQuery() const override;
void drop(ContextPtr context) override;
String getObjectMetadataPath(const String & object_name) const override;
time_t getObjectMetadataModificationTime(const String & object_name) const override;
String getDataPath() const override { return data_path; }
String getTableDataPath(const String & table_name) const override { return data_path + escapeForFileName(table_name) + "/"; }
String getTableDataPath(const ASTCreateQuery & query) const override { return getTableDataPath(query.table); }
String getMetadataPath() const override { return metadata_path; }
static ASTPtr parseQueryFromMetadata(Poco::Logger * log, ContextPtr context, const String & metadata_file_path, bool throw_on_error = true, bool remove_empty = false);
/// will throw when the table we want to attach already exists (in active / detached / detached permanently form)
void checkMetadataFilenameAvailability(const String & to_table_name) const;
void checkMetadataFilenameAvailabilityUnlocked(const String & to_table_name, std::unique_lock<std::mutex> &) const;
protected:
static constexpr const char * create_suffix = ".tmp";
static constexpr const char * drop_suffix = ".tmp_drop";
static constexpr const char * detached_suffix = ".detached";
using IteratingFunction = std::function<void(const String &)>;
void iterateMetadataFiles(ContextPtr context, const IteratingFunction & process_metadata_file) const;
ASTPtr getCreateTableQueryImpl(
const String & table_name,
ContextPtr context,
bool throw_on_error) const override;
ASTPtr getCreateQueryFromMetadata(const String & metadata_path, bool throw_on_error) const;
virtual void commitCreateTable(const ASTCreateQuery & query, const StoragePtr & table,
const String & table_metadata_tmp_path, const String & table_metadata_path, ContextPtr query_context);
virtual void removeDetachedPermanentlyFlag(ContextPtr context, const String & table_name, const String & table_metadata_path, bool attach) const;
const String metadata_path;
const String data_path;
};
}