High Undo_retention
878451May 17 2012 — edited May 21 2012Hi Fellows,
I am using Oracle 10g 10.2.0.5 with RAC 10G, using Solaris.
I am having some troubles with a specific querie, and it is taking a lot of time to finish with ORA-01555:
ORA-01555 caused by SQL statement below (SQL ID: 9h6zbrufuk2p7, Query Duration=63680 sec, SCN: 0x0002.6a1d8fef):
Thu May 17 05:14:04 BRT 2012
* I know that i suppose to increase the undo_retention to at least duration+1;
* my undo tablespaces have a lot of free space. The disks too.
* I know that i should analyze the querie and see the cost, but i want to explain to developer the reason i can“t set undo_retention too high.
What would happen if i set the undo_retention parameter to a high value as 64000 ?
Thanks in advance.