ClickHouse/src/Storages/StorageView.h

67 lines
2.2 KiB
C++

#pragma once
#include <Parsers/ASTSelectQuery.h>
#include <Parsers/IAST_fwd.h>
#include <Storages/IStorage.h>
namespace DB
{
class StorageView final : public IStorage
{
public:
StorageView(
const StorageID & table_id_,
const ASTCreateQuery & query,
const ColumnsDescription & columns_,
const String & comment);
std::string getName() const override { return "View"; }
bool isView() const override { return true; }
bool isParameterizedView() const { return is_parameterized_view; }
/// It is passed inside the query and solved at its level.
bool supportsSampling() const override { return true; }
bool supportsFinal() const override { return true; }
void read(
QueryPlan & query_plan,
const Names & column_names,
const StorageSnapshotPtr & storage_snapshot,
SelectQueryInfo & query_info,
ContextPtr context,
QueryProcessingStage::Enum processed_stage,
size_t max_block_size,
size_t num_streams) override;
void replaceQueryParametersIfParametrizedView(ASTPtr & outer_query);
static void replaceWithSubquery(ASTSelectQuery & select_query, ASTPtr & view_name, const StorageMetadataPtr & metadata_snapshot, const bool parameterized_view)
{
replaceWithSubquery(select_query, metadata_snapshot->getSelectQuery().inner_query->clone(), view_name, parameterized_view);
}
static void replaceWithSubquery(ASTSelectQuery & outer_query, ASTPtr view_query, ASTPtr & view_name, const bool parameterized_view);
static ASTPtr restoreViewName(ASTSelectQuery & select_query, const ASTPtr & view_name);
static String replaceQueryParameterWithValue (const String & column_name, const NameToNameMap & parameter_values, const NameToNameMap & parameter_types);
static String replaceValueWithQueryParameter (const String & column_name, const NameToNameMap & parameter_values);
void setParameterValues (NameToNameMap parameter_values_)
{
parameter_values = parameter_values_;
}
NameToNameMap getParameterValues() const
{
return parameter_types;
}
protected:
bool is_parameterized_view;
NameToNameMap parameter_values;
NameToNameMap parameter_types;
};
}