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CREATE TABLE INFOS
(
STUID VARCHAR2(7) NOT NULL,--学号 学号=‘S’+班号+2位序号
STUNAME VARCHAR2(10) NOT NULL,--姓名
GENDER VARCHAR2(2) NOT NULL,--性别
AGE NUMBER(2) NOT NULL, --年龄
SEAT NUMBER(2) NOT NULL,--座号
ENROLLDATE DATE, --入学时间
STUADDRESS VARCHAR2(50) DEFAULT "地址不详", --住址
CLASSNO VARCHAR2(4) NOT NULL --班号 班号=学期序号+班级序号
)
/
ALTER TABLE INFOS ADD CONSTRAINT PK_INFOS PRIMARY KEY(STUID)
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_GENDER
CHECK(GENDER = '男' OR GENDER ='女')
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_SEAT
CHECK(SEAT >= 0 AND SEAT <= 50)
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_AGE
CHECK(AGE >= 0 AND AGE <= 100)
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_CLASSNO
CHECK((CLASSNO >= '1001' AND CLASSNO <= '1999') OR
(CLASSNO >= '2011' AND CLASSNO <= '2999'))
/
ALTER TABLE INFOS ADD CONSTRAINTS UN_STUNAME UNIQUE(STUNAME)
/
SQL> create table "t_test" (id number);
Table created
SQL> insert into "t_test" values(1);
1 row inserted
SQL> select * from "t_test";
ID
----------
1
SQL> select * from t_test;
select * from t_test
ORA-00942: 表或视图不存在
SQL>