How to count distinct records based on some condition

Hi HANA Experts,

I want to count the distinct records based on some conditions. I tried with Counter, but it is not working as expected.

Please find the sample data.

I want to count the distinct records based on the below condition.

For counting Distinct Sales Order Number.

IF("RECORD_TYPE" ='SO' AND ("SO_NUMBER" != '') AND "FLAG" = ' ')

For counting Distinct Service Order Number

IF("RECORD_TYPE" ='SO' AND ("SR_NUMBER" != ' ') AND SO_STATUS = 'CLOSED')

Pls guide, how to achieve.

Thanks.