Sum distinct of previous records with condition

[varenich]

Hi,

Could you please advice how to make an expression or script to sum groupped distinct values with additional condition?

In each row of a segment I need to sum distinct (UniqueID) values (CRITICAL) from the row to begginning of a segment with additional check if UniqueIDEnd (of each previous record)  >[Check time] (of the current record)

Tried tons of ways, broke my head but  without success. Please help.

[varenich]

Thank you a lot!  Its exactly what I needed.