thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-26 17:41:59 +00:00
Code Issues Packages Projects Releases Wiki Activity

clickhouse: higher order functions: development [#CONV-7444].

Browse Source
This commit is contained in:
Michael Kolupaev 2013-05-20 15:42:57 +00:00
parent 70a13e3812
commit 26ed29cfeb
6 changed files with 285 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
dbms/include/DB/Columns/ColumnArray.h
View File

@ -27,9 +27,18 @@ public:
typedef ColumnVector<Offset_t> ColumnOffsets_t;
/** Создать пустой столбец массивов, с типом значений, как в столбце nested_column */
ColumnArray(ColumnPtr nested_column)
: data(nested_column), offsets(new ColumnOffsets_t)
explicit ColumnArray(ColumnPtr nested_column, ColumnPtr offsets_column = NULL)
: data(nested_column), offsets(offsets_column)
{
if (!offsets_column)
{
offsets = new ColumnOffsets_t;
}
else
{
if (!dynamic_cast<ColumnOffsets_t *>(&*offsets_column))
throw Exception("offsets_column must be a ColumnVector<UInt64>", ErrorCodes::ILLEGAL_COLUMN);
}
}
std::string getName() const { return "ColumnArray(" + data->getName() + ")"; }

6
dbms/include/DB/Columns/ColumnExpression.h
View File

@ -13,8 +13,8 @@ namespace DB
class ColumnExpression : public IColumnDummy
{
public:
ColumnExpression(size_t s_, ExpressionPtr expression_, const NamesAndTypes & arguments_, DataTypePtr return_type_)
: IColumnDummy(s_), expression(expression_), arguments(arguments_), return_type(return_type_) {}
ColumnExpression(size_t s_, ExpressionPtr expression_, const NamesAndTypes & arguments_, DataTypePtr return_type_, std::string return_name_)
: IColumnDummy(s_), expression(expression_), arguments(arguments_), return_type(return_type_), return_name(return_name_) {}
std::string getName() const { return "ColumnExpression"; }
ColumnPtr cloneDummy(size_t s_) const { return new ColumnExpression(s_, expression, arguments, return_type); }
@ -22,11 +22,13 @@ public:
ExpressionPtr & getExpression() { return expression; }
const NamesAndTypes & getArguments() const { return arguments; }
const DataTypePtr & getReturnType() const { return return_type; }
const std::string & getReturnName() const { return return_name; }
private:
ExpressionPtr expression;
NamesAndTypes arguments;
DataTypePtr return_type;
std::string return_name;
};
}

8
dbms/include/DB/Columns/IColumnDummy.h
View File

@ -18,13 +18,15 @@ public:
virtual ColumnPtr cloneDummy(size_t s_) const = 0;
ColumnPtr cloneEmpty() const { return cloneDummy(0); }
bool isConst() { return true; }
size_t size() const { return s; }
Field operator[](size_t n) const { throw Exception("Cannot get value from " + getName(), ErrorCodes::NOT_IMPLEMENTED); }
void get(size_t n, Field & res) const { throw Exception("Cannot get value from " + getName(), ErrorCodes::NOT_IMPLEMENTED); };
void insert(const Field & x) { throw Exception("Cannot insert element into " + getName(), ErrorCodes::NOT_IMPLEMENTED); }
void insertDefault() { ++s; }
size_t byteSize() const { return 0; }
int compareAt(size_t n, size_t m, const IColumn & rhs_) const { return 0; }
Field operator[](size_t n) const { throw Exception("Cannot get value from " + getName(), ErrorCodes::NOT_IMPLEMENTED); }
void get(size_t n, Field & res) const { throw Exception("Cannot get value from " + getName(), ErrorCodes::NOT_IMPLEMENTED); };
void insert(const Field & x) { throw Exception("Cannot insert element into " + getName(), ErrorCodes::NOT_IMPLEMENTED); }
StringRef getDataAt(size_t n) const { throw Exception("Method getDataAt is not supported for " + getName(), ErrorCodes::NOT_IMPLEMENTED); }
void insertData(const char * pos, size_t length) { throw Exception("Method insertData is not supported for " + getName(), ErrorCodes::NOT_IMPLEMENTED); }

264
dbms/include/DB/Functions/FunctionsHigherOrder.h Normal file
View File

@ -0,0 +1,264 @@
#pragma once
#include <DB/DataTypes/DataTypeArray.h>
#include <DB/DataTypes/DataTypeExpression.h>
#include <DB/DataTypes/DataTypesNumberFixed.h>
#include <DB/Columns/ColumnArray.h>
#include <DB/Columns/ColumnExpression.h>
#include <DB/Functions/IFunction.h>
namespace DB
{
/** Функции высшего порядка для массивов:
*
* arrayMap(x -> expression, array) - применить выражение к каждому элементу массива.
* arrayFilter(x -> predicate, array) - оставить в массиве только элементы, для которых выражение истинно.
* arrayCount(x -> predicate, array) - для скольки элементов массива выражение истинно.
* arrayExists(x -> predicate, array) - истинно ли выражение для хотя бы одного элемента массива.
*/
struct ArrayMapImpl
{
static bool needBooleanExpression() { return false; }
static DataTypePtr getReturnType(const DataTypePtr & expression_return, const DataTypePtr & array_element)
{
return new DataTypeArray(expression_return);
}
static ColumnPtr execute(ColumnArray * array, ColumnPtr mapped)
{
return new ColumnArray(mapped, array->getOffsetsColumn());
}
};
struct ArrayFilterImpl
{
static bool needBooleanExpression() { return true; }
static DataTypePtr getReturnType(const DataTypePtr & expression_return, const DataTypePtr & array_element)
{
if (!dynamic_cast<DataTypeUInt8>(&*expression_return))
throw Exception("Filter expression must be UInt8", ErrorCodes::TYPE_MISMATCH);
return new DataTypeArray(array_element);
}
static ColumnPtr execute(ColumnArray * array, ColumnPtr mapped)
{
ColumnVector<UInt8> * column_filter = dynamic_cast<ColumnVector<UInt8> *>(&*mapped);
if (!column_filter)
throw Exception("Unexpected type of filter column", ErrorCodes::ILLEGAL_COLUMN);
const IColumn::Filter & filter = column_filter->getData();
ColumnPtr filtered = array->getData().filter(filter);
const IColumn::Offsets_t & in_offsets = array->getOffsets();
ColumnArray::ColumnOffsets_t * column_offsets = new ColumnOffsets_t(in_offsets.size());
ColumnPtr column_offsets_ptr = column_offsets;
IColumn::Offsets_t & out_offsets = column_offsets->getData();
size_t in_pos = 0;
size_t out_pos = 0;
for (size_t i = 0; i < in_offsets.size(); ++i)
{
for (; in_pos < in_offsets[i]; ++in_pos)
{
if (filter[in_pos])
++out_pos;
}
out_offsets[i] = out_pos;
}
return new ColumnArray(filtered, column_offsets_ptr);
}
};
struct ArrayCountImpl
{
static bool needBooleanExpression() { return true; }
static DataTypePtr getReturnType(const DataTypePtr & expression_return, const DataTypePtr & array_element)
{
if (!dynamic_cast<DataTypeUInt8>(&*expression_return))
throw Exception("Filter expression must be UInt8", ErrorCodes::TYPE_MISMATCH);
return new DataUInt32;
}
static ColumnPtr execute(ColumnArray * array, ColumnPtr mapped)
{
ColumnVector<UInt8> * column_filter = dynamic_cast<ColumnVector<UInt8> *>(&*mapped);
if (!column_filter)
throw Exception("Unexpected type of filter column", ErrorCodes::ILLEGAL_COLUMN);
const IColumn::Filter & filter = column_filter->getData();
const IColumn::Offsets_t & offsets = array->getOffsets();
ColumnVector<UInt32> & out_column = new ColumnVector<UInt32>(offsets.size());
ColumnPtr out_column_ptr = out_column;
ColumnVector<UInt32>::Container_t & out_counts = out_column->getData();
size_t pos = 0;
for (size_t i = 0; i < offsets.size(); ++i)
{
size_t count = 0;
for (; pos < offsets[i]; ++pos)
{
if (filter[pos])
++count;
}
out_counts[i] = count;
}
return out_column_ptr;
}
};
struct ArrayExistsImpl
{
static bool needBooleanExpression() { return true; }
static DataTypePtr getReturnType(const DataTypePtr & expression_return, const DataTypePtr & array_element)
{
if (!dynamic_cast<DataTypeUInt8>(&*expression_return))
throw Exception("Filter expression must be UInt8", ErrorCodes::TYPE_MISMATCH);
return new DataUInt8;
}
static ColumnPtr execute(ColumnArray * array, ColumnPtr mapped)
{
ColumnVector<UInt8> * column_filter = dynamic_cast<ColumnVector<UInt8> *>(&*mapped);
if (!column_filter)
throw Exception("Unexpected type of filter column", ErrorCodes::ILLEGAL_COLUMN);
const IColumn::Filter & filter = column_filter->getData();
const IColumn::Offsets_t & offsets = array->getOffsets();
ColumnVector<UInt8> & out_column = new ColumnVector<UInt8>(offsets.size());
ColumnPtr out_column_ptr = out_column;
ColumnVector<UInt8>::Container_t & out_exists = out_column->getData();
size_t pos = 0;
for (size_t i = 0; i < offsets.size(); ++i)
{
UInt8 exists = 0;
for (; pos < offsets[i]; ++pos)
{
if (filter[pos])
{
exists = true;
break;
}
}
out_exists[i] = exists;
}
return out_column_ptr;
}
};
template <typename Impl, typename Name>
class FunctionArrayMapped : public IFunction
{
public:
/// Получить имя функции.
String getName() const
{
return Name::get();
}
void checkTypes(const DataTypes & arguments, const DataTypeExpression *& expression_type, const DataTypeArray *& array_type) {
if (arguments.size() != 2)
throw Exception("Number of arguments for function " + getName() + " doesn't match: passed "
+ Poco::NumberFormatter::format(arguments.size()) + ", should be 2.",
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
array_type = dynamic_cast<const DataTypeArray *>(&*arguments[1]);
if (!array_type)
throw Exception("Second argument for function " + getName() + " must be array. Found " + arguments[1]->getName() + " instead.", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
expression_type = dynamic_cast<const DataTypeExpression *>(&*arguments[0]);
if (!expression_type || expression_type.getArgumentTypes().size() != 1)
throw Exception("First argument for function " + getName() + " must be an expression with one argument. Found " + arguments[0]->getName() + " instead.", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
}
/// Вызывается, если хоть один агрумент функции - лямбда-выражение.
/// Для аргументов-лямбда-выражений определяет типы аргументов этих выражений.
void getLambdaArgumentTypes(DataTypes & arguments) const
{
const DataTypeArray * array_type;
const DataTypeExpression * expression_type;
checkTypes(arguments, expression_type, array_type);
arguments[0] = new DataTypeExpression(DataTypes(1, array_type->getNestedType()));
}
/// Получить типы результата по типам аргументов. Если функция неприменима для данных аргументов - кинуть исключение.
DataTypePtr getReturnType(const DataTypes & arguments) const
{
const DataTypeArray * array_type;
const DataTypeExpression * expression_type;
checkTypes(arguments, expression_type, array_type);
if (Impl::needBooleanExpression() && !dynamic_cast<const DataTypeUInt8 *>(&*expression_type->getReturnType()))
throw Exception("Expression for function " + getName() + " must return UInt8, found " + expression_type->getReturnType()->getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
return Impl::getReturnType(expression_type->getReturnType(), array_type->getNestedType());
}
/// Выполнить функцию над блоком.
void execute(Block & block, const ColumnNumbers & arguments, size_t result)
{
const ColumnArray * column_array = dynamic_cast<const ColumnArray *>(&*block.getByPosition(arguments[1]).column);
ColumnExpression * column_expression = dynamic_cast<ColumnExpression *>(&*block.getByPosition(arguments[1]).column);
Block temp_block;
Expression & expression = column_expression->getExpression();
Name argument_name = column_expression->getArguments()[0].first;
DataTypePtr element_type = column_expression->getArguments()[0].second;
/// Положим в блок аргумент выражения.
temp_block.insert(ColumnWithNameAndType(column_array->getDataPtr(), argument_name, element_type));
Names columns = expression.getRequiredColumns();
/// Положим в блок все нужные столбцы, размноженные по размерам массивов.
for (size_t i = 0; i < columns.size(); ++i)
{
const String & name = columns[i];
if (name == argument_name)
continue;
String replicated_name = "replicate(" + name + "," + block.getByPosition(arguments[1]).name + ")";
ColumnWithNameAndType replicated_column;
if (block.has(replicated_name))
{
replicated_column = block.getByName(replicated_name);
}
else
{
ColumnWithNameAndType needed_column = block.getByName(name);
replicated_column =
ColumnWithNameAndType(needed_column->replicate(column_array->getOffsets()), needed_column.type, replicated_name);
block.insert(replicated_column);
}
replicated_column.name = name;
temp_block.insert(replicated_column);
}
expression.execute(temp_block);
block.getByPosition(result).column = Impl::execute(temp_block.getByName(column_expression->getReturnName()).column);
}
};
struct NameArrayMap { static const char * get() { return "arrayMap"; } };
struct NameArrayFilter { static const char * get() { return "arrayFilter"; } };
struct NameArrayCount { static const char * get() { return "arrayCount"; } };
struct NameArrayExists { static const char * get() { return "arrayExists"; } };
typedef FunctionArrayMapped<ArrayMapImpl, NameArrayMap> FunctionArrayMap;
typedef FunctionArrayMapped<ArrayFilterImpl, NameArrayFilter> FunctionArrayFilter;
typedef FunctionArrayMapped<ArrayCountImpl, NameArrayCount> FunctionArrayCount;
typedef FunctionArrayMapped<ArrayExistsImpl, NameArrayExists> FunctionArrayExists;
}

2
dbms/include/DB/Functions/IFunction.h
View File

@ -34,7 +34,7 @@ public:
virtual DataTypePtr getReturnType(const DataTypes & arguments) const = 0;
/// Вызывается, если хоть один агрумент функции - лямбда-выражение.
/// Для аргументов-лямбда-выражений определяет типы аргументов этих выражений.
/// Для аргументов-лямбда-выражений определяет типы аргументов этих выражений и кладет результат в arguments.
virtual void getLambdaArgumentTypes(DataTypes & arguments) const
{
throw Exception("Function " + getName() + " can't have lambda-expressions as arguments", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);

1
dbms/include/DB/Interpreters/Expression.h
View File

@ -131,7 +131,6 @@ private:
typedef std::set<ASTPtr> SetOfASTs;
typedef std::map<ASTPtr, ASTPtr> MapOfASTs;
void init()
{
createAliasesDict(ast);