Suppose you create the following identity column table named id_phone.
CREATE TABLE id_phone( id_num INTEGER GENERATED ALWAYS AS IDENTITY (START WITH 1000 INCREMENT BY 10 MINVALUE 0 MAXVALUE 300000), phone INTEGER) UNIQUE PRIMARY INDEX(idnum);
After some time, you decide to use Teradata Unity to manage multiple Vantage instances, including one that includes the id_phone table. Because Teradata Unity requires deterministic behavior to ensure data consistency at each Vantage instance, you must remove the identity column attribute from the id_num column, but you must also retain the column and its data with id_phone because id_num is also the unique primary index for the table. You can use the following statement:
ALTER TABLE id_phone DROP id_num IDENTITY;
Column id_num in table id_phone is no longer an identity column, but it continues to be the unique primary index for the table.