[IT] 헷갈리기 쉬운 DBMS DML, DDL 예제 모음

DML (데이터 조작어)

SELECT

SELECT column1, column2, ... 
FROM table1 WHERE column1= 'value1' 
AND column2='value2'...

INSERT

INSERT INTO table1(column1, column2, ...)
VALUES ('value1', 'value2', ...)

UPDATE

UPDATE table1
SET column1=value1, column2='value2'...
WHERE column1= 'value1' AND column2='value2'...

DELETE

DELETE FROM table1
WHERE column1= 'value1' AND column2='value2'...

 

 

DDL (데이터 정의어)

CREATE TABLE

CREATE TABLE table1 (
   column1 number(3) NOT NULL,
   column2 varchar2(100) DEFAULT 'value1', ...
   )

DROP TABLE

DROP TABLE table1

RENAME TABLE

ALTER TABLE table1 RENAME TO table2

TRUNCATE TABLE

TRUNCATE TABLE table1

ALTER COLUMN (ADD, RENAME, MODIFY, DROP)

ALTER TABLE table1
ADD column3 varchar2(200)

ALTER TABLE table1
RENAME COLUMN column1 TO column2

ALTER TABLE table1
MODIFY column1 varchar2(150)

ALTER TABLE table1
DROP COLUMN column1