X++ select group by date

Hi,

It seems a stupid question but I tried multiple combination and failed.

In table A, I have thousands of records and I want to get all the different dates in this record.

In SQL, I know I can do it simply by

select date from TableA group by date

But now for X++ in AX

I tried

while select   A group by A.Date
{

}

without success. In MS doc, the examples are for number or counting no dates. I don't quite understand how to achieve my requirement.  Any help is grateful! Thanks!