**Use case**

Comparison between DateTime64 and DateTime / Date types is allowed but the behavior is confusing (it looks like used numerical comparison):

* from one side for zero-precision it works as expected (values compared as datetime-based ones): 

```sql
SELECT toTypeName(dt64) AS dt64_typename, dt64 = dt
FROM 
(
    SELECT 
        toDateTime64(toStartOfInterval(now(), toIntervalSecond(1), 'UTC'), 0, 'UTC') AS dt64,
        toStartOfInterval(now(), toIntervalSecond(1), 'UTC') AS dt
)

/*
┌─dt64_typename────────┬─equals(dt64, dt)─┐
│ DateTime64(0, 'UTC') │                1 │
└──────────────────────┴──────────────────┘
*/
```
* from another side for non-zero-precision its behavior is unexpected if not used explicit type conversion:

```sql
SELECT 
    toTypeName(dt64) AS dt64_typename,
    dt64 = dt,
    toDateTime(dt64) = dt,
    dt64 = toDateTime64(dt, 1, 'UTC')
FROM 
(
    SELECT 
        toDateTime64(toStartOfInterval(now(), toIntervalSecond(1), 'UTC'), 1, 'UTC') AS dt64,
        toStartOfInterval(now(), toIntervalSecond(1), 'UTC') AS dt
)
/*
┌─dt64_typename────────┬─equals(dt64, dt)─┬─equals(toDateTime(dt64), dt)─┬─equals(dt64, toDateTime64(dt, 1, 'UTC'))─┐
│ DateTime64(1, 'UTC') │                0 │                            1 │                                        1 │
└──────────────────────┴──────────────────┴──────────────────────────────┴──────────────────────────────────────────┘
*/
```

**Describe the solution you'd like**
I think this comparison either:
- should be not allowed and throw an exception to ask for user uses explicit conversion
- or make valid implicit conversion relying on datetime/date essence of values

auto column_converted = type_to_compare->createColumnConst(input_rows_count, converted);
            ColumnsWithTypeAndName tmp_columns
            {
                { left_const ? column_converted : col_left_untyped->getPtr(), type_to_compare, "" },
                { !left_const ? column_converted : col_right_untyped->getPtr(), type_to_compare, "" },
            };
            return executeImpl(tmp_columns, result_type, input_rows_count);
        }
    }
    ColumnPtr executeTuple(
        const DataTypePtr & result_type, const ColumnWithTypeAndName & c0, const ColumnWithTypeAndName & c1,
        size_t input_rows_count) const
    {
        /** We will lexicographically compare the tuples. This is done as follows:
          * x == y : x1 == y1 && x2 == y2 ...
          * x != y : x1 != y1 || x2 != y2 ...
          *
          * x < y:   x1 < y1 || (x1 == y1 && (x2 < y2 || (x2 == y2 ... && xn < yn))
          * x > y:   x1 > y1 || (x1 == y1 && (x2 > y2 || (x2 == y2 ... && xn > yn))
          * x <= y:  x1 < y1 || (x1 == y1 && (x2 < y2 || (x2 == y2 ... && xn <= yn))
          *
          * Recursive form:
          * x <= y:  x1 < y1 || (x1 == y1 && x_tail <= y_tail)
          *
          * x >= y:  x1 > y1 || (x1 == y1 && (x2 > y2 || (x2 == y2 ... && xn >= yn))
          */
        const size_t tuple_size = typeid_cast<const DataTypeTuple &>(*c0.type).getElements().size();
        if (0 == tuple_size)
            throw Exception("Comparison of zero-sized tuples is not implemented.", ErrorCodes::NOT_IMPLEMENTED);
        if (tuple_size != typeid_cast<const DataTypeTuple &>(*c1.type).getElements().size())