I started a deletion script that would delete about 340,000,000 rows from a database (I didn't realize it was that large). The script ran for too long so I killed the session. Then the rollback (I'm assuming that is what was happening next) took about 12 hrs. Today we had high log file sync wait time, high LGWR, DBWR and Buffer Cache Reads for about 30 minutes then everything went back to normal.
I'm trying to learn all of the things I did wrong and their consequences:
1. My delete was far too large. I should delete in smaller chunks and commit.
2. Did I go about killing the deletion properly?
3. Assuming I did the same thing, what should I have done after the rollback completed to prevent the log file sync and other issues?
Thanks!