Using the ALTER TABLE statement

The ALTER TABLE statement can be used to change the security policies of an object. SET ENCRYPT, DECRYPT, and REKEY clauses can be used to define encryption policies for tables, indexes or LOB columns; the ALTER TABLE statement is an online operation. The ALTER TABLE statement has the following syntax:

ALTER TABLE [ owner_name.]table_name
{ADD column-definition
|SET progress_table_attribute value
|SET[ENCRYPT WITH cipher
|DECRYPT
|ENCRYPT REKEY ]
|BUFFER_POOL{PRIMARY | ALTERNATE}
|ALTER [ COLUMN]column_name{ SET DEFAULT value
                               | DROP DEFAULT
                                | SET[NOT] NULL
                                | SET progress_column_attribute value}
                               |SET ENCRYPT WITH cipher
                                |SET DECRYPT
                                |ENCRYPT REKEY
                                | SET BUFFER_POOL{PRIMARY | ALTERNATE}}
|DROP COLUMN column_name { CASCADE | RESTRICT }
|ADD CONSTRAINT constraint_name ]{primary_key_definition
                                   |foreign_key_definition
                                  |uniqueness_constraint
                                   |check_constraint}[ AREA area_name ]
|DROP CONSTRAINT constraint_name[ CASCADE | RESTRICT]
|ALTER INDEX index_name{SET progress_index_attribute value
|SET ENCRYPT WITH cipher
|SET DECRYPT
                         |SET ENCRYPT REKEY
                         |SET BUFFER_POOL { PRIMARY | ALTERNATE }}
|RENAME {table_name TO new_table_name
|COLUMN column_name TO new_column_name
|INDEX index_name TO new_index_name}
};