楼上的神仙:
关于undo_retension,9i reference提到:
If an active transaction needs undo space and the undo tablespace does not have any free space, then the system will start reusing undo space that would have been retained. This may cause long queries to fail.
如果我的undo_retension设的不够大,但是undo tablespace很大,那undo_retension应该不会影响long queries吧?