5. Controlling Transaction Isolation

Sqoop uses read-committed transaction isolation in its mappers to import data. However, this may not be ideal for all ETL workflows, and you might want to reduce the isolation guarantees. Use the --relaxed-isolation option to instruct Sqoop to use read-uncommitted isolation level.

The read-uncommitted transaction isolation level is not supported on all databases, such as Oracle. Specifying the --relaxed-isolation may also not be supported on all databases.


There is no guarantee that two identical and subsequent uncommitted reads will return the same data.