#include #include #include namespace DB { /** ignore(...) is a function that takes any arguments, and always returns 0. */ class FunctionIgnore : public IFunction { public: static constexpr auto name = "ignore"; static FunctionPtr create(const Context &) { return std::make_shared(); } bool isVariadic() const override { return true; } size_t getNumberOfArguments() const override { return 0; } bool useDefaultImplementationForNulls() const override { return false; } String getName() const override { return name; } DataTypePtr getReturnTypeImpl(const DataTypes & /*arguments*/) const override { return std::make_shared(); } void executeImpl(Block & block, const ColumnNumbers &, size_t result, size_t input_rows_count) const override { block.getByPosition(result).column = DataTypeUInt8().createColumnConst(input_rows_count, 0u); } ColumnPtr getResultIfAlwaysReturnsConstantAndHasArguments(const Block &, const ColumnNumbers &) const override { return DataTypeUInt8().createColumnConst(1, 0u); } }; void registerFunctionIgnore(FunctionFactory & factory) { factory.registerFunction(); } }