Datapump

Use the flashback parameter to export and import a consistent dump

expdp <user>/<pwd> parfile=db_params.par

where db_params.par would look like this:

flashback_time=”to_timestamp (to_char (sysdate, ‘YYYY-MM-DD HH24:MI:SS’), ‘YYYY-MM-DD HH24:MI:SS’)”
directory=DATAPUMP_DIR
dumpfile=db_schema.dmp
schemas=(apps,test)

This performs a consistent dump of 2 schemas

Keeping the parameters in a file like this allows you to reuse it for the import:

impdp <user>/<pwd> parfile=db_params.par