>> Must say that for example NTFS supports writing compressed pages to disk
>> and does not fill it with 0, instead puts more data to the page.
>
> Well, when you tell that, I think that we don't need to duplicate this functionality
> and everybody who want database file to be compressed can just turn NTFS compression on.

Possibly the algorithm etc. is too general and doesn't offer the best
cost/benefit ratio for databases?

>> We
>> probably can do something like this - when adding new record/version to
>> the page compress it and when result does not fit, use another page for
>> that record/version.
>
> Isn't it exactly the way the engine already use? AFAIK, if compressed record doesn't
> fit to free space on the primary page, it is chained to other page.
>

Regards,
Thomas