ClickHouse/src/DataTypes/FieldToDataType.h
2020-04-03 18:14:31 +03:00

36 lines
1.2 KiB
C++

#pragma once
#include <Common/FieldVisitors.h>
namespace DB
{
class IDataType;
using DataTypePtr = std::shared_ptr<const IDataType>;
/** For a given Field returns the minimum data type that allows this value to be stored.
* Note that you still have to convert Field to corresponding data type before inserting to columns
* (for example, this is necessary to convert elements of Array to common type).
*/
class FieldToDataType : public StaticVisitor<DataTypePtr>
{
public:
DataTypePtr operator() (const Null & x) const;
DataTypePtr operator() (const UInt64 & x) const;
DataTypePtr operator() (const UInt128 & x) const;
DataTypePtr operator() (const Int64 & x) const;
DataTypePtr operator() (const Float64 & x) const;
DataTypePtr operator() (const String & x) const;
DataTypePtr operator() (const Array & x) const;
DataTypePtr operator() (const Tuple & tuple) const;
DataTypePtr operator() (const DecimalField<Decimal32> & x) const;
DataTypePtr operator() (const DecimalField<Decimal64> & x) const;
DataTypePtr operator() (const DecimalField<Decimal128> & x) const;
DataTypePtr operator() (const AggregateFunctionStateData & x) const;
};
}