| 1 | #pragma once |
|---|---|
| 2 | |
| 3 | #include <Columns/IColumnDummy.h> |
| 4 | |
| 5 | |
| 6 | namespace DB |
| 7 | { |
| 8 | |
| 9 | class ColumnNothing final : public COWHelper<IColumnDummy, ColumnNothing> |
| 10 | { |
| 11 | private: |
| 12 | friend class COWHelper<IColumnDummy, ColumnNothing>; |
| 13 | |
| 14 | ColumnNothing(size_t s_) |
| 15 | { |
| 16 | s = s_; |
| 17 | } |
| 18 | |
| 19 | ColumnNothing(const ColumnNothing &) = default; |
| 20 | |
| 21 | public: |
| 22 | const char * getFamilyName() const override { return "Nothing"; } |
| 23 | MutableColumnPtr cloneDummy(size_t s_) const override { return ColumnNothing::create(s_); } |
| 24 | |
| 25 | bool canBeInsideNullable() const override { return true; } |
| 26 | |
| 27 | bool structureEquals(const IColumn & rhs) const override |
| 28 | { |
| 29 | return typeid(rhs) == typeid(ColumnNothing); |
| 30 | } |
| 31 | }; |
| 32 | |
| 33 | } |
| 34 |