ClickHouse/src/Functions/FunctionsBitToArray.cpp

338 lines
11 KiB
C++

#include <Columns/ColumnArray.h>
#include <Columns/ColumnString.h>
#include <Columns/ColumnVector.h>
#include <DataTypes/DataTypeArray.h>
#include <DataTypes/DataTypeString.h>
#include <DataTypes/DataTypesNumber.h>
#include <Functions/FunctionFactory.h>
#include <Functions/IFunction.h>
#include <IO/WriteBufferFromVector.h>
#include <IO/WriteHelpers.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
extern const int ILLEGAL_COLUMN;
}
/** Functions for an unusual conversion to a string or array:
*
* bitmaskToList - takes an integer - a bitmask, returns a string of degrees of 2 separated by a comma.
* for example, bitmaskToList(50) = '2,16,32'
*
* bitmaskToArray(x) - Returns an array of powers of two in the binary form of x. For example, bitmaskToArray(50) = [2, 16, 32].
*
*/
namespace
{
class FunctionBitmaskToList : public IFunction
{
public:
static constexpr auto name = "bitmaskToList";
static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionBitmaskToList>(); }
String getName() const override
{
return name;
}
size_t getNumberOfArguments() const override { return 1; }
bool isInjective(const ColumnsWithTypeAndName &) const override { return true; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
const DataTypePtr & type = arguments[0];
if (!isInteger(type))
throw Exception("Cannot format " + type->getName() + " as bitmask string", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
return std::make_shared<DataTypeString>();
}
bool useDefaultImplementationForConstants() const override { return true; }
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t /*input_rows_count*/) const override
{
ColumnPtr res;
if (!((res = executeType<UInt8>(arguments))
|| (res = executeType<UInt16>(arguments))
|| (res = executeType<UInt32>(arguments))
|| (res = executeType<UInt64>(arguments))
|| (res = executeType<Int8>(arguments))
|| (res = executeType<Int16>(arguments))
|| (res = executeType<Int32>(arguments))
|| (res = executeType<Int64>(arguments))))
throw Exception("Illegal column " + arguments[0].column->getName()
+ " of argument of function " + getName(),
ErrorCodes::ILLEGAL_COLUMN);
return res;
}
private:
template <typename T>
inline static void writeBitmask(T x, WriteBuffer & out)
{
using UnsignedT = make_unsigned_t<T>;
UnsignedT u_x = x;
bool first = true;
while (u_x)
{
UnsignedT y = u_x & (u_x - 1);
UnsignedT bit = u_x ^ y;
u_x = y;
if (!first)
writeChar(',', out);
first = false;
writeIntText(T(bit), out);
}
}
template <typename T>
ColumnPtr executeType(const ColumnsWithTypeAndName & columns) const
{
if (const ColumnVector<T> * col_from = checkAndGetColumn<ColumnVector<T>>(columns[0].column.get()))
{
auto col_to = ColumnString::create();
const typename ColumnVector<T>::Container & vec_from = col_from->getData();
ColumnString::Chars & data_to = col_to->getChars();
ColumnString::Offsets & offsets_to = col_to->getOffsets();
size_t size = vec_from.size();
data_to.resize(size * 2);
offsets_to.resize(size);
WriteBufferFromVector<ColumnString::Chars> buf_to(data_to);
for (size_t i = 0; i < size; ++i)
{
writeBitmask<T>(vec_from[i], buf_to);
writeChar(0, buf_to);
offsets_to[i] = buf_to.count();
}
buf_to.finalize();
return col_to;
}
return nullptr;
}
};
class FunctionBitmaskToArray : public IFunction
{
public:
static constexpr auto name = "bitmaskToArray";
static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionBitmaskToArray>(); }
String getName() const override
{
return name;
}
size_t getNumberOfArguments() const override { return 1; }
bool isInjective(const ColumnsWithTypeAndName &) const override { return true; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
if (!isInteger(arguments[0]))
throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(),
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
return std::make_shared<DataTypeArray>(arguments[0]);
}
bool useDefaultImplementationForConstants() const override { return true; }
template <typename T>
bool tryExecute(const IColumn * column, ColumnPtr & out_column) const
{
using UnsignedT = make_unsigned_t<T>;
if (const ColumnVector<T> * col_from = checkAndGetColumn<ColumnVector<T>>(column))
{
auto col_values = ColumnVector<T>::create();
auto col_offsets = ColumnArray::ColumnOffsets::create();
typename ColumnVector<T>::Container & res_values = col_values->getData();
ColumnArray::Offsets & res_offsets = col_offsets->getData();
const typename ColumnVector<T>::Container & vec_from = col_from->getData();
size_t size = vec_from.size();
res_offsets.resize(size);
res_values.reserve(size * 2);
for (size_t row = 0; row < size; ++row)
{
UnsignedT x = vec_from[row];
while (x)
{
UnsignedT y = x & (x - 1);
UnsignedT bit = x ^ y;
x = y;
res_values.push_back(bit);
}
res_offsets[row] = res_values.size();
}
out_column = ColumnArray::create(std::move(col_values), std::move(col_offsets));
return true;
}
else
{
return false;
}
}
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t /*input_rows_count*/) const override
{
const IColumn * in_column = arguments[0].column.get();
ColumnPtr out_column;
if (tryExecute<UInt8>(in_column, out_column) ||
tryExecute<UInt16>(in_column, out_column) ||
tryExecute<UInt32>(in_column, out_column) ||
tryExecute<UInt64>(in_column, out_column) ||
tryExecute<Int8>(in_column, out_column) ||
tryExecute<Int16>(in_column, out_column) ||
tryExecute<Int32>(in_column, out_column) ||
tryExecute<Int64>(in_column, out_column))
return out_column;
throw Exception("Illegal column " + arguments[0].column->getName()
+ " of first argument of function " + getName(),
ErrorCodes::ILLEGAL_COLUMN);
}
};
class FunctionBitPositionsToArray : public IFunction
{
public:
static constexpr auto name = "bitPositionsToArray";
static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionBitPositionsToArray>(); }
String getName() const override
{
return name;
}
size_t getNumberOfArguments() const override { return 1; }
bool isInjective(const ColumnsWithTypeAndName &) const override { return true; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
if (!isInteger(arguments[0]))
throw Exception(ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT,
"Illegal type {} of argument of function {}",
getName(),
arguments[0]->getName());
return std::make_shared<DataTypeArray>(std::make_shared<DataTypeUInt64>());
}
bool useDefaultImplementationForConstants() const override { return true; }
template <typename T>
ColumnPtr executeType(const IColumn * column) const
{
const ColumnVector<T> * col_from = checkAndGetColumn<ColumnVector<T>>(column);
if (!col_from)
return nullptr;
auto result_array_values = ColumnVector<UInt64>::create();
auto result_array_offsets = ColumnArray::ColumnOffsets::create();
auto & result_array_values_data = result_array_values->getData();
auto & result_array_offsets_data = result_array_offsets->getData();
auto & vec_from = col_from->getData();
size_t size = vec_from.size();
result_array_offsets_data.resize(size);
result_array_values_data.reserve(size * 2);
using UnsignedType = make_unsigned_t<T>;
for (size_t row = 0; row < size; ++row)
{
UnsignedType x = static_cast<UnsignedType>(vec_from[row]);
if constexpr (is_big_int_v<UnsignedType>)
{
size_t position = 0;
while (x)
{
if (x & 1)
result_array_values_data.push_back(position);
x >>= 1;
++position;
}
}
else
{
while (x)
{
result_array_values_data.push_back(getTrailingZeroBitsUnsafe(x));
x &= (x - 1);
}
}
result_array_offsets_data[row] = result_array_values_data.size();
}
auto result_column = ColumnArray::create(std::move(result_array_values), std::move(result_array_offsets));
return result_column;
}
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t /*input_rows_count*/) const override
{
const IColumn * in_column = arguments[0].column.get();
ColumnPtr result_column;
if (!((result_column = executeType<UInt8>(in_column))
|| (result_column = executeType<UInt16>(in_column))
|| (result_column = executeType<UInt32>(in_column))
|| (result_column = executeType<UInt32>(in_column))
|| (result_column = executeType<UInt64>(in_column))
|| (result_column = executeType<UInt128>(in_column))
|| (result_column = executeType<UInt256>(in_column))
|| (result_column = executeType<Int8>(in_column))
|| (result_column = executeType<Int16>(in_column))
|| (result_column = executeType<Int32>(in_column))
|| (result_column = executeType<Int64>(in_column))
|| (result_column = executeType<Int128>(in_column))
|| (result_column = executeType<Int256>(in_column))))
{
throw Exception(ErrorCodes::ILLEGAL_COLUMN,
"Illegal column {} of first argument of function {}",
arguments[0].column->getName(),
getName());
}
return result_column;
}
};
}
void registerFunctionsBitToArray(FunctionFactory & factory)
{
factory.registerFunction<FunctionBitPositionsToArray>();
factory.registerFunction<FunctionBitmaskToArray>();
factory.registerFunction<FunctionBitmaskToList>();
}
}