Hello Aki,

maybe you stumbled over one of the less-intuitive features of SQL.
The result of MAX(x) or MIN(x) is defined to be NULL (expressed as '?'
in SQL Studio) if the set of values from which the MAX/MIN values
is calculated is empty.

One can explain that the minumum/maximum of nothing is not nothing,
but unknown in the SQL sense.

SQL aggregation functions (MAX/MIN/COUNT/SUM/...) do return 
always a value.

Oh, and no, there is no relation to some re-naming going on :-)

Alexander Schr�der
SAP DB, SAP Labs Berlin 

> -----Original Message-----
> From: Aki Karjalainen [mailto:[EMAIL PROTECTED]
> Sent: Friday, September 26, 2003 11:49 AM
> To: [EMAIL PROTECTED]
> Subject: Problem with max(date) function
> 
> 
> 
> 
> Hello.
> 
> I'm having problems with select max(productdate) from mytable. SQL
> studio only returns "?". However, select min(productdate) from mytable
> executes ok.
> 
> I've made sure no date in my table is not null. Is there a bug in max
> date comparison?
> 
> 
> ps. Does this have anything to do with the fact that sapdb is 
> now known
> as maxdb? :)
> 
> 
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