I'm in the process of creating a Wikidata use case example to present and I have chosen a subject that I hope is of interest by many persons: sports.

I want to present a query for the the athletes that are ACTIVE TODAY in a certain discipline, e.g. "soccer".

From the results of the query on the players I have had to 

1) filter out the retired (I want only the active ones)

2) filter out the death persons

The second is required since the date for the end of career is not always available, especially for athletes of the past. 

Here the point:

I found athletes with the "Date of born" but with NO "date of death". So a query on the age show me athletes up to 149 years old.

Since the oldest know person was 122, what about to set "date of death = unknown value" for all the persons resulting older such age ?

Thanks in advance for you opinion

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