17.05 - DROP column_name - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Syntax and Examples

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Release Date
January 2021
Content Type
Programming Reference
Publication ID
B035-1144-175K
Language
English (United States)

Removes the named column from the table. 
You cannot drop the QITS column from a queue table. For a column-partitioned table, Vantage drops the specified column from its column partition. 
If the specified column is the only column in the column partition, and the partition is not the only column partition, Vantage drops the partition. You cannot drop a column partition with a single column when it is the only column partition defined for the table or join index. You cannot drop a column in use as the begin column or end column of a derived period column.

For information about dropping temporal columns, see Teradata Vantage™ - Temporal Table Support , B035-1182 .

IDENTITY
Removes the identity column attribute for the named column from the table. 
The specification of IDENTITY is optional.
You can drop an identity column from an existing table. 
When you use Teradata Unity, you cannot do a bulk data load insert of rows into a table that has an identity column. However, you can specify this option to drop only the identity column attribute while retaining the column and data. This is useful when the identity column for a table is also its unique primary index. Teradata Unity provides its own mechanism for generating identity column-like values for tables that require the identity column functionality. For additional information, see the Teradata Unity documentation.