ClickHouse/src/Parsers/ASTBackupQuery.h
2022-05-08 10:37:02 +02:00

94 lines
3.3 KiB
C++

#pragma once
#include <Parsers/IAST.h>
#include <Parsers/ASTQueryWithOnCluster.h>
namespace DB
{
using Strings = std::vector<String>;
using DatabaseAndTableName = std::pair<String, String>;
/** BACKUP { TABLE [db.]table_name [AS [db.]table_name_in_backup] [PARTITION[S] partition_expr [,...]] |
* DICTIONARY [db.]dictionary_name [AS [db.]dictionary_name_in_backup] |
* DATABASE database_name [AS database_name_in_backup] [EXCEPT TABLES ...] |
* TEMPORARY TABLE table_name [AS table_name_in_backup] |
* ALL TEMPORARY TABLES [EXCEPT ...] |
* ALL DATABASES [EXCEPT ...] } [,...]
* [ON CLUSTER 'cluster_name']
* TO { File('path/') |
* Disk('disk_name', 'path/')
* [SETTINGS base_backup = {File(...) | Disk(...)}]
*
* RESTORE { TABLE [db.]table_name_in_backup [AS [db.]table_name] [PARTITION[S] partition_expr [,...]] |
* DICTIONARY [db.]dictionary_name_in_backup [AS [db.]dictionary_name] |
* DATABASE database_name_in_backup [AS database_name] [EXCEPT TABLES ...] |
* TEMPORARY TABLE table_name_in_backup [AS table_name] |
* ALL TEMPORARY TABLES [EXCEPT ...] |
* ALL DATABASES [EXCEPT ...] } [,...]
* [ON CLUSTER 'cluster_name']
* FROM {File(...) | Disk(...)}
*
* Notes:
* RESTORE doesn't drop any data, it either creates a table or appends an existing table with restored data.
* This behaviour can cause data duplication.
* If appending isn't possible because the existing table has incompatible format then RESTORE will throw an exception.
*
* The "AS" clause is useful to backup or restore under another name.
* For the BACKUP command this clause allows to set the name which an object will have inside the backup.
* And for the RESTORE command this clause allows to set the name which an object will have after RESTORE has finished.
*/
class ASTBackupQuery : public IAST, public ASTQueryWithOnCluster
{
public:
enum Kind
{
BACKUP,
RESTORE,
};
Kind kind = Kind::BACKUP;
enum ElementType
{
TABLE,
DATABASE,
ALL_DATABASES,
};
struct Element
{
ElementType type;
DatabaseAndTableName name;
DatabaseAndTableName new_name;
bool is_temp_db = false;
ASTs partitions;
std::set<String> except_list;
void setDatabase(const String & new_database);
};
using Elements = std::vector<Element>;
static void setDatabase(Elements & elements, const String & new_database);
void setDatabase(const String & new_database) { setDatabase(elements, new_database); }
Elements elements;
ASTPtr backup_name;
ASTPtr settings;
/// Base backup. Only differences made after the base backup will be included in a newly created backup,
/// so this setting allows to make an incremental backup.
ASTPtr base_backup_name;
/// List of cluster's hosts' IDs if this is a BACKUP/RESTORE ON CLUSTER command.
ASTPtr cluster_host_ids;
String getID(char) const override;
ASTPtr clone() const override;
void formatImpl(const FormatSettings & format, FormatState &, FormatStateStacked) const override;
ASTPtr getRewrittenASTWithoutOnCluster(const WithoutOnClusterASTRewriteParams &) const override;
};
}