컬럼 및 제약 조건은 ALTER 구문의 ADD [ATTRIBUTE | COLUMN] 예약어를 사용하여 추가할 수 있다.
ALTER [
table_type
] table_name
ADD [ ATTRIBUTE
| COLUMN
] attr_definition
| table_constraint_definition
[ { ,
attr_definition
| class_constraint }_
]
[ INHERIT
resolution
[ { , resolution }_
] ] [ ;
]
ALTER
[ table_type ] table_name
ADD CLASS ATTRIBUTE table_attr_definition
[ {, class_attr_definition
}_ ]
[ INHERIT resolution [ { ,
resolution }_ ] ] [ ;
]
table_type:
[TABLE | CLASS]
[VIEW | VCLASS]
resolution:
[ TABLE
] attr_mthd_name
OF
superclass_name
[ AS
alias
]
table_constraint_definition :
[ CONSTRAINT constraint_name
] [ UNIQUE | PRIMARY
KEY | FOREIGN KEY]
(attribute_name
[{, attribute_name }
...])
ALTER TABLE athlete
ADD COLUMN age INT;
ALTER TABLE athlete ADD
COLUMN age INT DEFAULT 0 NOT NULL;
ALTER TABLE athlete
ADD COLUMN retire CHAR(1) SHARED 'N';
ATLER TABLE athlete
ADD COLUMN phone VARCHAR(13) DEFAULT '000-0000-0000';
ALTER TABLE company ADD CONSTRAINT
pk_id PRIMARY KEY (comp_id);
ALTER TABLE nation ADD
CONSTRAINT u_name UNIQUE (name);