15.10 - RELEASE ROWS - Teradata Database

Teradata Database SQL Data Definition Language Syntax and Examples

prodname
Teradata Database
vrm_release
15.10
created_date
December 2015
category
Programming Reference
featnum
B035-1144-151K

Removes the logically deleted rows from a load isolated (LDI) table or a join index. You use this option to reclaim the space occupied by the deleted rows. You should collect statistics when you perform this operation on an LDI table or a join index. Reclaiming space on a regular basis improves query performance on the LDI table or a join index. This operation physically deletes those rows that are marked as logically deleted. The corresponding secondary indexes are maintained.

You must have the DROP TABLE privilege to perform this operation.

An EXCLUSIVE lock is placed on the table to perform the deletion.

DELETED
Optionally, the DELETED keyword can be specified for readability.
AND RESET LOAD IDENTITY
The RowLoadID of the rows is set to 0. The version number of the table is incremented and the CurrLoadID value is set to 0.
If this option is not specified, the version number of the table is not changed.

Example: Remove Logically Deleted Rows

ALTER TABLE lditab1 RELEASE ROWS;

Example: Remove Logically Deleted Rows and Reset RowLoadID

ALTER TABLE lditabl2 RELEASE DELETED ROWS AND RESET LOAD IDENTITY;