You may need to recreate a data table to:
- Change a default PI to a defined PI for a nonempty table.
- Add or remove a PI for a nonempty table.
- Change the PI to a different PI for a nonempty table.
- Change a NUPI to a UPI in a populated table when there is no USI (however, usually you would just create the USI on the table, and then alter it).
- Redefine the partitioning of a populated table. In some cases, you can still use ALTER TABLE; see “ALTER TABLE” in Teradata Vantage™ SQL Data Definition Language Syntax and Examples, B035-1144.
- Change a data type attribute that affects existing data. For rules on changing data types, see “ALTER TABLE” in Teradata Vantage™ SQL Data Definition Language Syntax and Examples, B035-1144.
- Define or delete COMPRESS storage attributes for an existing column.
- Add columns that would otherwise exceed the maximum for the number of columns defined during the life of a table.
- Move the table to another database or user.
- Change the groupings of columns into column partitions.
It is best practice to access a table via a view, especially for tables used by multiple users.
Use the SHOW TABLE or SHOW IN XML TABLE request to display the current table definition, which you can then modify and submit.