Are you doing this in a production database? If so, what sort of downtime are you allowed?
Unless you have partitioned tables, you wouldn't want to use COALESCE PARTITION. Coalescing a tablespae combines contiguous free extents in a tablespace into one large extent.
What sort of tablespaces do you have? Locally managed or dictionary managed?
Justin
Distributed Database Consulting, Inc.
http://www.ddbcinc.com/askDDBC