Question: I have an export expdp job failing
with an ORA-01555 error:
ORA-31693: Table data
object "BAXXDB"."MS_DATA" failed to load/unload and
is being skipped due to error:
ORA-02354: error in exporting/importing data
ORA-01555: snapshot too old: rollback segment
number 20 with name "_SYSSMU20_4037596720$" too small
All of the other tables (before and after) exported fine,
it is just this one table. How do I fix this
error in expdp?
There are several
solutions to this ORA-01555 problem.
Re-schedule long-running queries when
the system has less DML load.
the size of your rollback segment (undo) size. The
ORA-01555 snapshot too old also relates to your setting
automatic undo retention.
Increase the size of
your undo_retention parameter. Automatic
undo management depends upon the
undo_retention parameter, which defines
how long Oracle should try to keep committed
transactions in UNDO segments. However, the
undo_retention parameter is only a
You must also have an
UNDO tablespace that’s large enough to handle the amount
of UNDO you will be generating/holding, or you will get
"ORA-01555: Snapshot too old, rollback segment too
If a table
has any columns defined a LOB? If so see MOSC Note:
452341.1. You can offload CLOB tables using
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