How to Get Available space on Database using a Dynamic Query:-
EXEC(N'USE ' + @dbname + N' select [FILE_SIZE_MB] =
convert(decimal(12,2),round(size/128.000,2)),
[SPACE_USED_MB] =
convert(decimal(12,2),round(fileproperty(name,''SpaceUsed'')/
128.000,2)),
[FREE_SPACE_MB] =
convert(decimal(12,2),round((size-
fileproperty(name,''SpaceUsed''))/128.000,2)),
[DEVICE_NAME] = left(NAME,15)
from dbo.sysfiles;')
