Could anyone answer this question, please?

I'm running the stored procedure sp_spaceused on a complete database on a
weekly basis.

As the 'data' and 'index' sizes increase, the 'unused' amount maintains
about 10% of 'data plus index', as I've got it set on automatic increase at
10%. Therefore, the 'reserved' amount increases, as would be expected.

The number of Mb set for the 'database size' remains constant, so the
'unallocated space' reduces, which would also be expected.

The questiion is:

By subtracting the 'reserved' number of Mb from the 'database size',
I get an answer which varies by 2 to 2.5 % les than the 'unallocated
space' each week.

I'm wondering if there is a bug somwhere, and would be interested if anyone
else has encountered this problem.

Phil Shuttleworth, DBA, IT Services, UCE.
MS Sql Server LazyDBA home page