**Use case**

Viewing binary data such as bitmasks, hashes, internal representation of IEEE-754 numbers, etc.
Mostly for debugging.

**Describe the solution you'd like**

Similar to `hex`/`unhex`.

`bin` - returns a string with `0` and `1`. Bits are in "human" order, most significant first. Most significant zero bits are not printed (except the case with single zero).

**Describe alternatives you've considered**

Now I have to run interactive `python` from command line, but I will be more happy using ClickHouse.

**Caveats**

The name `bin` may suggest that the function will "split data into bins" but it is completely unrelated.
size_t current_size = strnlen(pos_in, n);
                memcpySmallAllowReadWriteOverflow15(pos, pos_in, current_size);
                pos += current_size;
                *pos = '\0';
                out_offsets[i] = ++pos - begin;
                pos_in += n;
            }
            out_vec.resize(pos - begin);
            if (!out_offsets.empty() && out_offsets.back() != out_vec.size())
                throw Exception("Column size mismatch (internal logical error)", ErrorCodes::LOGICAL_ERROR);
            col_res = std::move(col_str);
            return true;
        }
        else
        {
            return false;
        }
    }
    ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t ) const override
    {
        const IColumn * column = arguments[0].column.get();
        ColumnPtr res_column;
        if (tryExecuteFixedString(column, res_column) || tryExecuteString(column, res_column))
            return res_column;
        throw Exception("Illegal column " + arguments[0].column->getName()
                        + " of argument of function " + getName(),
                        ErrorCodes::ILLEGAL_COLUMN);
    }
};
class FunctionIPv6CIDRToRange : public IFunction