My Oracle Support Banner

DataPump Import (IMPDP) Seems To Hang When Importing Referential Constraints (Doc ID 2308198.1)

Last updated on SEPTEMBER 14, 2024

Applies to:

Oracle Database - Enterprise Edition - Version 10.1.0.2 and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.

Goal

DataPump Import (impdp) is running slow when loading referential constraints:

Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/REF_CONSTRAINT


The slowness of import when importing data with constraints enabled is introduced when validating the integrity of all existing data.

This behavior can introduce a serious performance problem when the amount of data to be checked is large and also there is a large number of constraints involved in this process.

The time spent on the ref_constraint load is directly proportional to the amount of data involved in the load operation.
Enabling the constraints in SQL*Plus or SQL*Loader will take same amount of time because by default, the constraint is created with "ENABLE VALIDATE" option;
VALIDATE ensures that existing data conforms to the constraint. So it is taking long time to validate the integrity of the constraint and appears to hang.

Solution

To view full details, sign in with your My Oracle Support account.

Don't have a My Oracle Support account? Click to get started!

In this Document
Goal
Solution


My Oracle Support provides customers with access to over a million knowledge articles and a vibrant support community of peers and Oracle experts.