ClickHouse/src/Databases/DatabaseOnDisk.h
SuperDJY dd2972b8c3
return fake create query when executing show create table on system's tables. (#31391)
* clarify that cannot show create table of system's tables

* clarify that cannot show create table of system's tables in the document

* bypass test style-check for required `database=currentDatabase()` because `show create table` do not have condition

* rename supportsShowCreateTable to isSystemStorage

* build fake create query for show create table of system's tables

* fix tests for show create table on system's table:

1. only build fake create query when cannot get real query
2. only test rocksdb when it's enabled.

* fix test for show create table system.tables

* fix test for ASTCreateQuery set table and database

* change to LOGICAL_ERROR when cannot get in_memory metadata

Co-authored-by: tavplubix <tavplubix@gmail.com>

* implement common getCreateQueryFromStorage

Co-authored-by: tavplubix <tavplubix@gmail.com>
2021-11-19 13:25:55 +03:00

107 lines
4.0 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 force_restore);
/** 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);
/* 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.getTable()); }
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;
void modifySettingsMetadata(const SettingsChanges & settings_changes, ContextPtr query_context);
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;
ASTPtr getCreateQueryFromStorage(const String & table_name, const StoragePtr & storage, 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;
/// For alter settings.
std::mutex modify_settings_mutex;
};
}