For a given database, I want to know space information by table. The tables are not all in the default dbspace for the database.

What is the easiest non-instrusive way to do this? oncheck -pe?

You can select it from system table (I'm no sure what table is) for all information If you afraid that it's old data you can update statistics low for table it will update information in system table

If you know how to construct such a query for non-fragmented tables, I would appreciate knowing as well. I have looked at all of the catalog tables and can't find the information I need.

The only way that I can see for determining this information is by using "oncheck -pe".

use sysmaster database :

select tabname , <systabinfo.fileds_you_want> from systabnames n,
systabinfo i
where n.partnum = i.ti_partnum

from systabinfo you should choose
ti_nextns ( number of extents )
ti_nptotal ( space allocated )
ti_npused ( space used )
ti_npdata ( space used by data , indexes excluded )
some tables that you know that have not too much indexes
low ti_npdata and high and almost npused = nptotal
will be probably wasting space and you should unload
all data , recreate the table e load data again
and then build the indexes

i´d like to know the meaning of ti_flags ....