Defragmenting Tablespaces

-> The free extents in a tablespace are stored in the table fet$.
-> Each record identifies each free extent the start address and the end
-> address. Deleting rows from this table and updating other
-> corresponding rows to appropriate addresses defragments the
-> tablespace. I have used this without any problem on temporary
-> tablespaces which tend to get fragmented very often.
->
-> Krishnan
-> PS: Try this first on a database which u can crash. This approach is
-> obviously unsupported.

You are coalescing, not defragging. You can do the same thing by figuring out the largest adjoining segments and asking Oracle to create tables exactly that size. The only problem here is if you have any non adjoining large segments it will use those 1st. Received on Wed Oct 26 1994 - 21:29:00 CET