I noticed that one of the tablespaces on a database that I support was growing rapidly. So I checked the to see which tables in the tablespace were using the most space by selecting the npages from syscat.tables. I also have a tool I use which shows the overall available space for the tablespace. The tool shows used pages for this tablespace to be 950720 pages. However, when I add all the npages values up I only got 25644.
Is there some other method I could use to see what tables are using the majority space? Is there an explanation why these numbers would be so different? I have a script that runs on the AIX box, and it agrees with the tool values.