ClickHouse/src/Functions/FunctionHelpers.cpp
2022-04-16 04:54:04 +02:00

322 lines
12 KiB
C++

#include <Functions/FunctionHelpers.h>
#include <Functions/IFunction.h>
#include <Columns/ColumnTuple.h>
#include <Columns/ColumnString.h>
#include <Columns/ColumnFixedString.h>
#include <Columns/ColumnNullable.h>
#include <Columns/ColumnLowCardinality.h>
#include <Common/assert_cast.h>
#include <DataTypes/DataTypeNullable.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_COLUMN;
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
extern const int SIZES_OF_ARRAYS_DOESNT_MATCH;
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
}
const ColumnConst * checkAndGetColumnConstStringOrFixedString(const IColumn * column)
{
if (!isColumnConst(*column))
return {};
const ColumnConst * res = assert_cast<const ColumnConst *>(column);
if (checkColumn<ColumnString>(&res->getDataColumn())
|| checkColumn<ColumnFixedString>(&res->getDataColumn()))
return res;
return {};
}
Columns convertConstTupleToConstantElements(const ColumnConst & column)
{
const ColumnTuple & src_tuple = assert_cast<const ColumnTuple &>(column.getDataColumn());
const auto & src_tuple_columns = src_tuple.getColumns();
size_t tuple_size = src_tuple_columns.size();
size_t rows = column.size();
Columns res(tuple_size);
for (size_t i = 0; i < tuple_size; ++i)
res[i] = ColumnConst::create(src_tuple_columns[i], rows);
return res;
}
ColumnWithTypeAndName columnGetNested(const ColumnWithTypeAndName & col)
{
if (col.type->isNullable())
{
const DataTypePtr & nested_type = static_cast<const DataTypeNullable &>(*col.type).getNestedType();
if (!col.column)
{
return ColumnWithTypeAndName{nullptr, nested_type, col.name};
}
else if (const auto * nullable = checkAndGetColumn<ColumnNullable>(*col.column))
{
const auto & nested_col = nullable->getNestedColumnPtr();
return ColumnWithTypeAndName{nested_col, nested_type, col.name};
}
else if (const auto * const_column = checkAndGetColumn<ColumnConst>(*col.column))
{
const auto * nullable_column = checkAndGetColumn<ColumnNullable>(const_column->getDataColumn());
ColumnPtr nullable_res;
if (nullable_column)
{
const auto & nested_col = nullable_column->getNestedColumnPtr();
nullable_res = ColumnConst::create(nested_col, col.column->size());
}
else
{
nullable_res = makeNullable(col.column);
}
return ColumnWithTypeAndName{ nullable_res, nested_type, col.name };
}
else
throw Exception("Illegal column for DataTypeNullable", ErrorCodes::ILLEGAL_COLUMN);
}
return col;
}
ColumnsWithTypeAndName createBlockWithNestedColumns(const ColumnsWithTypeAndName & columns)
{
ColumnsWithTypeAndName res;
for (const auto & col : columns)
res.emplace_back(columnGetNested(col));
return res;
}
void validateArgumentType(const IFunction & func, const DataTypes & arguments,
size_t argument_index, bool (* validator_func)(const IDataType &),
const char * expected_type_description)
{
if (arguments.size() <= argument_index)
throw Exception("Incorrect number of arguments of function " + func.getName(),
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
const auto & argument = arguments[argument_index];
if (!validator_func(*argument))
throw Exception("Illegal type " + argument->getName() +
" of " + std::to_string(argument_index) +
" argument of function " + func.getName() +
" expected " + expected_type_description,
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
}
namespace
{
void validateArgumentsImpl(const IFunction & func,
const ColumnsWithTypeAndName & arguments,
size_t argument_offset,
const FunctionArgumentDescriptors & descriptors)
{
for (size_t i = 0; i < descriptors.size(); ++i)
{
const auto argument_index = i + argument_offset;
if (argument_index >= arguments.size())
{
break;
}
const auto & arg = arguments[i + argument_offset];
const auto & descriptor = descriptors[i];
if (int error_code = descriptor.isValid(arg.type, arg.column); error_code != 0)
throw Exception("Illegal type of argument #" + std::to_string(argument_offset + i + 1) // +1 is for human-friendly 1-based indexing
+ (descriptor.argument_name ? " '" + std::string(descriptor.argument_name) + "'" : String{})
+ " of function " + func.getName()
+ (descriptor.expected_type_description ? String(", expected ") + descriptor.expected_type_description : String{})
+ (arg.type ? ", got " + arg.type->getName() : String{}),
error_code);
}
}
}
int FunctionArgumentDescriptor::isValid(const DataTypePtr & data_type, const ColumnPtr & column) const
{
if (type_validator_func && (data_type == nullptr || !type_validator_func(*data_type)))
return ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT;
if (column_validator_func && (column == nullptr || !column_validator_func(*column)))
return ErrorCodes::ILLEGAL_COLUMN;
return 0;
}
void validateFunctionArgumentTypes(const IFunction & func,
const ColumnsWithTypeAndName & arguments,
const FunctionArgumentDescriptors & mandatory_args,
const FunctionArgumentDescriptors & optional_args)
{
if (arguments.size() < mandatory_args.size() || arguments.size() > mandatory_args.size() + optional_args.size())
{
auto join_argument_types = [](const auto & args, const String sep = ", ")
{
String result;
for (const auto & a : args)
{
using A = std::decay_t<decltype(a)>;
if constexpr (std::is_same_v<A, FunctionArgumentDescriptor>)
{
if (a.argument_name)
result += "'" + std::string(a.argument_name) + "' : ";
if (a.expected_type_description)
result += a.expected_type_description;
}
else if constexpr (std::is_same_v<A, ColumnWithTypeAndName>)
result += a.type->getName();
result += sep;
}
if (!args.empty())
result.erase(result.end() - sep.length(), result.end());
return result;
};
throw Exception("Incorrect number of arguments for function " + func.getName()
+ " provided " + std::to_string(arguments.size())
+ (!arguments.empty() ? " (" + join_argument_types(arguments) + ")" : String{})
+ ", expected " + std::to_string(mandatory_args.size())
+ (!optional_args.empty() ? " to " + std::to_string(mandatory_args.size() + optional_args.size()) : "")
+ " (" + join_argument_types(mandatory_args)
+ (!optional_args.empty() ? ", [" + join_argument_types(optional_args) + "]" : "")
+ ")",
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
}
validateArgumentsImpl(func, arguments, 0, mandatory_args);
if (!optional_args.empty())
validateArgumentsImpl(func, arguments, mandatory_args.size(), optional_args);
}
std::pair<std::vector<const IColumn *>, const ColumnArray::Offset *>
checkAndGetNestedArrayOffset(const IColumn ** columns, size_t num_arguments)
{
assert(num_arguments > 0);
std::vector<const IColumn *> nested_columns(num_arguments);
const ColumnArray::Offsets * offsets = nullptr;
for (size_t i = 0; i < num_arguments; ++i)
{
const ColumnArray::Offsets * offsets_i = nullptr;
if (const ColumnArray * arr = checkAndGetColumn<const ColumnArray>(columns[i]))
{
nested_columns[i] = &arr->getData();
offsets_i = &arr->getOffsets();
}
else
throw Exception("Illegal column " + columns[i]->getName() + " as argument of function", ErrorCodes::ILLEGAL_COLUMN);
if (i == 0)
offsets = offsets_i;
else if (*offsets_i != *offsets)
throw Exception("Lengths of all arrays passed to aggregate function must be equal.", ErrorCodes::SIZES_OF_ARRAYS_DOESNT_MATCH);
}
return {nested_columns, offsets->data()};
}
bool areTypesEqual(const IDataType & lhs, const IDataType & rhs)
{
const auto & lhs_name = lhs.getName();
const auto & rhs_name = rhs.getName();
return lhs_name == rhs_name;
}
bool areTypesEqual(const DataTypePtr & lhs, const DataTypePtr & rhs)
{
return areTypesEqual(*lhs, *rhs);
}
ColumnPtr wrapInNullable(const ColumnPtr & src, const ColumnsWithTypeAndName & args, const DataTypePtr & result_type, size_t input_rows_count)
{
ColumnPtr result_null_map_column;
/// If result is already nullable.
ColumnPtr src_not_nullable = src;
if (src->onlyNull())
return src;
else if (const auto * nullable = checkAndGetColumn<ColumnNullable>(*src))
{
src_not_nullable = nullable->getNestedColumnPtr();
result_null_map_column = nullable->getNullMapColumnPtr();
}
for (const auto & elem : args)
{
if (!elem.type->isNullable())
continue;
/// Const Nullable that are NULL.
if (elem.column->onlyNull())
{
assert(result_type->isNullable());
return result_type->createColumnConstWithDefaultValue(input_rows_count);
}
if (isColumnConst(*elem.column))
continue;
if (const auto * nullable = checkAndGetColumn<ColumnNullable>(*elem.column))
{
const ColumnPtr & null_map_column = nullable->getNullMapColumnPtr();
if (!result_null_map_column) //-V1051
{
result_null_map_column = null_map_column;
}
else
{
MutableColumnPtr mutable_result_null_map_column = IColumn::mutate(std::move(result_null_map_column));
NullMap & result_null_map = assert_cast<ColumnUInt8 &>(*mutable_result_null_map_column).getData();
const NullMap & src_null_map = assert_cast<const ColumnUInt8 &>(*null_map_column).getData();
for (size_t i = 0, size = result_null_map.size(); i < size; ++i)
result_null_map[i] |= src_null_map[i];
result_null_map_column = std::move(mutable_result_null_map_column);
}
}
}
if (!result_null_map_column)
return makeNullable(src);
return ColumnNullable::create(src_not_nullable->convertToFullColumnIfConst(), result_null_map_column);
}
NullPresence getNullPresense(const ColumnsWithTypeAndName & args)
{
NullPresence res;
for (const auto & elem : args)
{
res.has_nullable |= elem.type->isNullable();
res.has_null_constant |= elem.type->onlyNull();
}
return res;
}
bool isDecimalOrNullableDecimal(const DataTypePtr & type)
{
WhichDataType which(type);
if (which.isDecimal())
return true;
if (!which.isNullable())
return false;
return isDecimal(assert_cast<const DataTypeNullable *>(type.get())->getNestedType());
}
}