You can use the following procedures and tools to detect and correct errors in tables that use partitioning and referencing. (For more information, see “Partitioned and Nonpartitioned Primary Indexes” and “FOREIGN KEY … REFERENCES Constraints” in Teradata Vantage™ - Database Design, B035-1094.)
|IF you want to …||THEN …|
|correct a partitioning expression that is causing transaction rollbacks due to an evaluation error (such as divide by zero)||do one of the following:
|find invalid table states or internal structures||run the CheckTable utility LEVEL 3 command.|
|regenerate only the headers in a table with partitioning||use the ALTER TABLE … REVALIDATE statement.|
|validate a column-partitioned table or join index||use the REVALIDATE option of the ALTER TABLE request.|
|for a table with partitioning:
||use the ALTER TABLE … REVALIDATE WITH DELETE/INSERT[INTO] statement.
REVALIDATE changes the table version.
|reset the state of RI tables after an ARC RESTORE operation||run the ARC utility REVALIDATE REFERENCES FOR command. For more information, see Teradata® Archive/Recovery Utility Reference, B035-2412.|
|find corrupt rows after running an update or delete operation using WITH NO CHECK OPTION on tables with RI constraints||submit the RI Validation Query, structured as:
SELECT DISTINCTchildtablename .* FROM childtablename,parenttablename WHERE childtablename .fkcol NOT IN (SELECT pkcol FROM parenttablename ) AND childtablename .fkcol IS NOT NULL;
This query reports every row in the Child table with an FK value that does not have a matching PK value. (FK nulls are excluded because it is not possible to determine the values they represent.)
|purify a Child table for which corrupt rows were reported by the RI Validation Query||delete from the Child table any reported rows as soon as possible to maintain the integrity of your database.|