ClickHouse/src/Core/SortDescription.cpp

#include <Core/SortDescription.h>
#include <Core/Block.h>
#include <IO/Operators.h>

namespace DB
{

void dumpSortDescription(const SortDescription & description, const Block & header, WriteBuffer & out)
{
    bool first = true;

    for (const auto & desc : description)
    {
        if (!first)
            out << ", ";
        first = false;

        if (!desc.column_name.empty())
            out << desc.column_name;
        else
        {
            if (desc.column_number < header.columns())
                out << header.getByPosition(desc.column_number).name;
            else
                out << "?";

            out << " (pos " << desc.column_number << ")";
        }

        if (desc.direction > 0)
            out << " ASC";
        else
            out << " DESC";

        if (desc.with_fill)
            out << " WITH FILL";
    }
}

}