I need to be able to tell how much free space is left in a given tablespace.
I know there is a data dictionary view dba_free_space, but this only shows the
amount of unallocated space in the tablespace i.e. not given to extents.
We have designed the tablespaces to give the objects in them large initial extents
and much smaller next extents in an attempt to get all our data goes into the first
extent (a tuning tip).
How can we find out how much of an extent is used WITHOUT putting statistics on the
table (as this is slow and will affect the optimisation method)? The database must
be up 24hrs a day so no non-operational time is available.
