Unable to import constraints using IMPDP in Oracle 19c

Question

I am using

impdp user/password@PDB directory=data_pump_dir tables=tablename dumpfile=DP_3.dmp logfile=card.log parallel=6

there are 2 tables: Table A and Table B

the tables are restored correctly, but for some reason, the constraints are not restored:

ORA-39083: Object type REF_CONSTRAINT:"user"."TABLE_B_FK" failed to create with error:
ORA-02298: cannot validate (user.TABLE_B_FK) - parent keys not found

the parent key is Table A's primary key, which should have been restored as well.

is it because the table that I backup up was quite large and was constantly changing while the export was running?

Answer 1

If you did not specifically ask for a consistent export by providing the CONSISTENT=Y option or values for the FLASHBACK_SCN/FLASHBACK_TIMESTAMP parameters, your dumpfile contains a consistent state of the tables but at different points of time per table and some values required for the FK constraint may be missing.

Use one of the options from above to avoid this situation.