Gavin Scott wrote:
>
> I wonder how many databases still use YYMMDD date formats (i.e. with date
> windowing) and have fields of this type as sort items?
>
> Dates have always been popular sort items since as long as the current date
> is used then new entries will sort/be added to the end of the sorted chain
> in the database, which is an efficient operation in Image.
>
> Of course now that a two digit YY date starts with "00", every DBPUT is
> going to have to read the entire dataset serially (backwards) before it
> finds the appropriate place in the chain at which to insert the entry!
>
> This will of course quietly result in amazingly bad performance rather than
> any overt failure of the application.
>
> The Growthpower "hang" described earlier this morning sounds a lot like what
> one would expect in the case of this kind of problem.

Growthpower uses a nasty Kludge for Sorted Dates. 991231 is followed by
A00101. Jan 2000 thru Dec 2009 is A00101 to A91231. Jan 2010 thru Dec
2019 is B00101 to B91231. And so on.

This, of course absolutely KILLS Powerhouse dictionaries that define
these areas as DATE. You have to overlay DATE-FIELD with DATE-FIELD-X
and then perform a convoluted extract.