mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-13 18:02:24 +00:00
91 lines
3.5 KiB
C++
91 lines
3.5 KiB
C++
#pragma once
|
|
|
|
#include <ext/shared_ptr_helper.h>
|
|
|
|
#include <Common/OptimizedRegularExpression.h>
|
|
#include <Storages/IStorage.h>
|
|
#include <Interpreters/Context.h>
|
|
|
|
|
|
namespace DB
|
|
{
|
|
|
|
/** A table that represents the union of an arbitrary number of other tables.
|
|
* All tables must have the same structure.
|
|
*/
|
|
class StorageMerge final : public ext::shared_ptr_helper<StorageMerge>, public IStorage
|
|
{
|
|
friend struct ext::shared_ptr_helper<StorageMerge>;
|
|
public:
|
|
std::string getName() const override { return "Merge"; }
|
|
|
|
bool isRemote() const override;
|
|
|
|
/// The check is delayed to the read method. It checks the support of the tables used.
|
|
bool supportsSampling() const override { return true; }
|
|
bool supportsPrewhere() const override { return true; }
|
|
bool supportsFinal() const override { return true; }
|
|
bool supportsIndexForIn() const override { return true; }
|
|
|
|
QueryProcessingStage::Enum getQueryProcessingStage(const Context &, QueryProcessingStage::Enum /*to_stage*/, const ASTPtr &) const override;
|
|
|
|
Pipes read(
|
|
const Names & column_names,
|
|
const SelectQueryInfo & query_info,
|
|
const Context & context,
|
|
QueryProcessingStage::Enum processed_stage,
|
|
size_t max_block_size,
|
|
unsigned num_streams) override;
|
|
|
|
void checkAlterIsPossible(const AlterCommands & commands, const Settings & /* settings */) override;
|
|
|
|
/// you need to add and remove columns in the sub-tables manually
|
|
/// the structure of sub-tables is not checked
|
|
void alter(const AlterCommands & params, const Context & context, TableStructureWriteLockHolder & table_lock_holder) override;
|
|
|
|
bool mayBenefitFromIndexForIn(const ASTPtr & left_in_operand, const Context & query_context) const override;
|
|
|
|
private:
|
|
String source_database;
|
|
OptimizedRegularExpression table_name_regexp;
|
|
Context global_context;
|
|
|
|
using StorageWithLockAndName = std::tuple<StoragePtr, TableStructureReadLockHolder, String>;
|
|
using StorageListWithLocks = std::list<StorageWithLockAndName>;
|
|
|
|
StorageListWithLocks getSelectedTables(const String & query_id, const Settings & settings) const;
|
|
|
|
StorageMerge::StorageListWithLocks getSelectedTables(
|
|
const ASTPtr & query, bool has_virtual_column, const String & query_id, const Settings & settings) const;
|
|
|
|
template <typename F>
|
|
StoragePtr getFirstTable(F && predicate) const;
|
|
|
|
DatabaseTablesIteratorPtr getDatabaseIterator() const;
|
|
|
|
const NamesAndTypesList & getVirtuals() const override;
|
|
|
|
protected:
|
|
StorageMerge(
|
|
const StorageID & table_id_,
|
|
const ColumnsDescription & columns_,
|
|
const String & source_database_,
|
|
const String & table_name_regexp_,
|
|
const Context & context_);
|
|
|
|
Block getQueryHeader(const Names & column_names, const SelectQueryInfo & query_info,
|
|
const Context & context, QueryProcessingStage::Enum processed_stage);
|
|
|
|
Pipes createSources(
|
|
const SelectQueryInfo & query_info, const QueryProcessingStage::Enum & processed_stage,
|
|
const UInt64 max_block_size, const Block & header, const StorageWithLockAndName & storage_with_lock,
|
|
Names & real_column_names,
|
|
const std::shared_ptr<Context> & modified_context, size_t streams_num, bool has_table_virtual_column,
|
|
bool concat_streams = false);
|
|
|
|
void convertingSourceStream(const Block & header, const Context & context, ASTPtr & query,
|
|
Pipe & pipe, QueryProcessingStage::Enum processed_stage);
|
|
};
|
|
|
|
}
|