I'm trying to spool a report on a large, OLTP, database. I'm getting a lot of 'snapshot too old' stuff even though I've reduced the # of days I'm requesting down to one from thirty.
ORA-01555: snapshot too old: rollback segment number 7 with name "R05" too small.
We have a large rollback segment and when I use it, it still breaks as follows:
BASE-DON> SET TRANSACTION USE ROLLBACK SEGMENT large_rbs;
BASE-DON> select distinct c.clientnumber,
ERROR at line 24:
ORA-01555: snapshot too old: rollback segment number 23 with name "R21" too small
When I SET TRANSACTIO READ ONLY, it still breaks. I'm not understanding what is going
on here. Can somebody give me a reason this happens?