16.20 - Referential Integrity When a Table Is Inconsistent - Teradata Database - Teradata Vantage NewSQL Engine

Teradata Vantage™ SQL Data Definition Language Detailed Topics

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Release Date
March 2019
Content Type
Programming Reference
Publication ID
B035-1184-162K
Language
English (United States)

While a table is marked as inconsistent, no updates, inserts, or deletes are permitted. The table is fully usable only when the inconsistencies are resolved. This restriction is true for both hard and soft (Referential Constraint) referential integrity constraints.

It is possible that the user either intends to or must revert to a definition of a table which results in an inconsistent reference on that table. The Archive and Restore operations are the most common cause of such inconsistencies.

After the child table is archived, the parent table can be dropped.

When the child table is restored, the parent table no longer exists. The normal ALTER TABLE DROP FOREIGN KEY request does not work, because the parent table references cannot be resolved.

You can use the DROP INCONSISTENT REFERENCES option to remove these inconsistent references from a table.

The syntax is as follows.

     ALTER TABLE  database_name.table_name  DROP INCONSISTENT REFERENCES

You must have DROP privilege on the target table of the request to perform this option, which removes all inconsistent internal indexes used to establish references.