On average 50K rows a day are inserted into these 5 tables, and the majority of "msg" values is over 4K so the clobs are stored out-of-line. The clobs are only SELECTed, not updated (I know I should change the pctversion to 0). Every day at 1AM a script runs to delete rows from each of the 5 tables with msg_date older than 14 days. So each day 50K rows are being deleted from these 5 tables.
My problem is this: despite the daily deletes, my lob tablespace (tbs_lobs) is continuing to grow in size. Why are the lobindex and lobsegment segments of the deleted lobs not being reused by newly inserted lobs? I dont think changing the pctversion will alter this behavior. Does anyone have any ideas? TIA!
however, I seem to be running into results different than the testing shown on that post. Tom claims the segments should be reused by the tables the segments are allocated to w/o needing to truncate any tables. I will continue to work on my end to understand what are the possible causes of my dilemma.