ClickHouse/src/Interpreters/FillingRow.cpp

146 lines
3.7 KiB
C++

#include <Interpreters/FillingRow.h>
#include <Common/FieldVisitorsAccurateComparison.h>
#include <IO/Operators.h>
namespace DB
{
bool less(const Field & lhs, const Field & rhs, int direction)
{
if (direction == -1)
return applyVisitor(FieldVisitorAccurateLess(), rhs, lhs);
return applyVisitor(FieldVisitorAccurateLess(), lhs, rhs);
}
bool equals(const Field & lhs, const Field & rhs)
{
return applyVisitor(FieldVisitorAccurateEquals(), lhs, rhs);
}
FillingRow::FillingRow(const SortDescription & sort_description_)
: sort_description(sort_description_)
{
row.resize(sort_description.size());
}
bool FillingRow::operator<(const FillingRow & other) const
{
for (size_t i = 0; i < sort_description.size(); ++i)
{
if ((*this)[i].isNull() || other.row[i].isNull() || equals(row[i], other.row[i]))
continue;
return less(row[i], other.row[i], getDirection(i));
}
return false;
}
bool FillingRow::operator==(const FillingRow & other) const
{
for (size_t i = 0; i < sort_description.size(); ++i)
if (!equals(row[i], other.row[i]))
return false;
return true;
}
bool FillingRow::operator>=(const FillingRow & other) const
{
return !(*this < other);
}
bool FillingRow::isNull() const
{
for (const auto & field : row)
if (!field.isNull())
return false;
return true;
}
std::pair<bool, bool> FillingRow::next(const FillingRow & to_row)
{
const size_t row_size = size();
size_t pos = 0;
/// Find position we need to increment for generating next row.
for (; pos < row_size; ++pos)
if (!row[pos].isNull() && !to_row.row[pos].isNull() && !equals(row[pos], to_row.row[pos]))
break;
if (pos == row_size || less(to_row.row[pos], row[pos], getDirection(pos)))
return {false, false};
/// If we have any 'fill_to' value at position greater than 'pos',
/// we need to generate rows up to 'fill_to' value.
for (size_t i = row_size - 1; i > pos; --i)
{
auto & fill_column_desc = getFillDescription(i);
if (fill_column_desc.fill_to.isNull() || row[i].isNull())
continue;
Field next_value = row[i];
fill_column_desc.step_func(next_value);
if (less(next_value, fill_column_desc.fill_to, getDirection(i)))
{
row[i] = next_value;
initFromDefaults(i + 1);
return {true, true};
}
}
auto next_value = row[pos];
getFillDescription(pos).step_func(next_value);
if (less(to_row.row[pos], next_value, getDirection(pos)) || equals(next_value, getFillDescription(pos).fill_to))
return {false, false};
row[pos] = next_value;
if (equals(row[pos], to_row.row[pos]))
{
bool is_less = false;
for (size_t i = pos + 1; i < row_size; ++i)
{
const auto & fill_from = getFillDescription(i).fill_from;
if (!fill_from.isNull())
row[i] = fill_from;
else
row[i] = to_row.row[i];
is_less |= less(row[i], to_row.row[i], getDirection(i));
}
return {is_less, true};
}
initFromDefaults(pos + 1);
return {true, true};
}
void FillingRow::initFromDefaults(size_t from_pos)
{
for (size_t i = from_pos; i < sort_description.size(); ++i)
row[i] = getFillDescription(i).fill_from;
}
String FillingRow::dump() const
{
WriteBufferFromOwnString out;
for (size_t i = 0; i < row.size(); ++i)
{
if (i != 0)
out << ", ";
out << row[i].dump();
}
return out.str();
}
WriteBuffer & operator<<(WriteBuffer & out, const FillingRow & row)
{
out << row.dump();
return out;
}
}