
select toDateTime64(-86400 ,9,'UTC') ==  1969-12-31 00:00:00.000000000

select toDateTime64(-86400.00 ,9,'UTC') ==  1970-01-01 00:00:00.000000000 


However, I expect both outputs to be same. 

Version affected : 22.8
static IFunction::Monotonicity get(const IDataType & type, const Field &, const Field &)
    {
        if (type.isValueRepresentedByNumber())
            return { .is_monotonic = true, .is_always_monotonic = true };
        else
            return {};
    }
};
/** The monotonicity for the `toString` function is mainly determined for test purposes.
  * It is doubtful that anyone is looking to optimize queries with conditions `toString(CounterID) = 34`.
  */
struct ToStringMonotonicity
{
    static bool has() { return true; }