How to dynamically number UserID and PurchaseDate

Hi Smitu30 

If you want to have a dynamic sort, you need to build a measure and use Rankx function. 

I build a table like yours to have a test.

Measure:

Measure = RANKX(FILTER(ALLSELECTED('Table'),'Table'[UserID]=MAX('Table'[UserID])),CALCULATE(MAX('Table'[PurchaseDate])),,ASC)

Result is as below.

Default:

Filter Date>=2020/8/1:

The max function in filter will return to a value = value in current row. So your filter will return to a table which values are all equal to current row.

Ex: Filter(Table,'Table'[UserID]=MAX('Table'[UserID])), IF current row's UserID = 1,so it will return to the table as below and calculate the rank of 'Table'[PurchaseDate] in this table. And you can refer to the blog as below to learn more about context filter and row filter.

For more info:

Filter 

row-context-and-filter-context-in-dax

You can download the pbix file from this link: How to dynamically number UserID and PurchaseDate

Best Regards,

Rico Zhou

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