Although you can change some of the characteristics of a table and retain the ability to restore or copy selected partitions to it, other operations on a partitioned table render the table unsuitable for selected partition restorations.
The following table definition changes do not invalidate subsequent restorations of selected partitions for the targeted or referenced tables.
- Altering table-level options that are not related to the semantic integrity of the table, including the following.
- Fallback protection (see ALTER TABLE and FALLBACK).
- Journaling attributes (see Transient Journaling).
- Free space percentage.
- Data block size (see IMMEDIATE DATABLOCKSIZE).
Also see CREATE TABLE (Table Options Clause) for more information about these options.
- Altering the partitioning expression. See Rules For Altering a Partitioning For a Table and CREATE TABLE (Index Definition Clause) for more information about these options.
- Altering either column-level or table-level CHECK constraints. See Adding and Dropping CHECK Constraints and CREATE TABLE (Column Definition Clause) for more information about these options.
When the target and source are different systems, you must repeat each of the previously listed operations on the affected tables of the target system to ensure that the two are kept in synchrony.
The following ALTER TABLE operations do make any future restore or copy operations of selected partitions for targeted or referenced tables non-valid.
- Adding or dropping columns (see Dropping Columns From a Table and Adding Columns To a Table).
- Altering the definition of existing columns (excluding the exceptions noted in the previous list).
- Adding, dropping, or modifying referential integrity relationships between tables (see Adding or Dropping Standard Referential Integrity Constraints).
See Teradata Vantage™ - Database Administration, B035-1093 for complete warnings, procedures, and other information related to partial restoration of partitions.