ClickHouse/src/Parsers/ASTSubquery.h
2021-01-26 10:29:12 +08:00

43 lines
1005 B
C++

#pragma once
#include <Parsers/ASTWithAlias.h>
namespace DB
{
/** SELECT subquery
*/
class ASTSubquery : public ASTWithAlias
{
public:
// Stored the name when the subquery is defined in WITH clause. For example:
// WITH (SELECT 1) AS a SELECT * FROM a AS b; cte_name will be `a`.
std::string cte_name;
/** Get the text that identifies this element. */
String getID(char) const override { return "Subquery"; }
ASTPtr clone() const override
{
const auto res = std::make_shared<ASTSubquery>(*this);
ASTPtr ptr{res};
res->children.clear();
for (const auto & child : children)
res->children.emplace_back(child->clone());
return ptr;
}
void updateTreeHashImpl(SipHash & hash_state) const override;
protected:
void formatImplWithoutAlias(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
void appendColumnNameImpl(WriteBuffer & ostr) const override;
};
}