Hi.
I'm on ASE 15.0.3. I have some hypothetical questions relating to the size of a DUMP DATABASE. I'm sure I could find this out myself through testing, but that would be very inconvenient for me.
Suppose I create a database at 100GB, and about 80GB of that is being used. If I do an uncompressed DUMP DATABASE, I'm thinking the resulting file ought to be about 80GB.
Now suppose I issue DELETE commands to delete many rows out of a lot of different tables. Suppose that brings the database down to 20GB used. If I then do an uncompressed DUMP DATABASE, what should I expect for the resulting file size? I'm thinking that some database pages would have gone totally empty, and so those would now be excluded from the dump. On the other hand, the tables might still be pretty "fragmented" or whatever you'd call it, and there'd be lots of pages that are only partially filled, and those pages would still be included. What if I then did a REORG REBUILD on all the tables? Would the uncompressed dump file size go down dramatically?
Finally, what if I were to do those dumps as compressed dumps instead of uncompressed? Would a "partially filled" page tend to get compressed more than a "totally filled" page? Seems like that might depend on the compression algorithm being used, as well as what bytes actually reside in the "unused" portion of an ASE page. Any clues?
Thanks!
- John.