I work with a former DB2 DBA who is requesting me to insert a space character in a primary key field. I don't like this idea one bit, but I'm not sure how best to approach it.

The table will be a reference table.

My arguments so far:
- Space character and null values are indistinguishable to humans, therefore loses meaning
- A distinct character value is more meaningful
- 'Cuz I said so....

Help!
I need some strong arguments!

thanks