ORACLE_____DDL 数据定义语言(DATA DEFINITION LANGUAGE)

--建表

CREATE TABLE STUDENT(

ST_ID NUMBER(7),

ST_NAME VARCHAR2(20),

ST_SEX VARCHAR2(2),

ST_JOIN_DATE DATE,

ST_HOBBIES VARCHAR2(100)

)

--添加列  ADD()

ALTER TABLE STUDENT ADD(ST_AGE NUMBER(3))

--删除列 DROP COLUMN *

ALTER TABLE STUDENT DROP COLUMN ST_AGE;

--查询表

SELECT * FROM STUDENT

--修改列名 RENAME COLUMN  * TO * 

ALTER TABLE STUDENT RENAME COLUMN ST_HOBBIES TO ST_HOBBY

--修改字段属性  MODIFY *  property

ALTER TABLE STUDENT MODIFY ST_HOBBY NUMBER(10)

--修改表名  RENAME * TO *

RENAME STUDENT TO STUDENTS

--删除表  DROP TABLE *

DROP TABLE STUDENTS