设置成number类型primary key,然后建立sequence来实现自增--syntax
ALTER TABLE table_name add CONSTRAINT constraint_name PRIMARY KEY (column1, column2, ... column_n);
ALTER TABLE table_name add CONSTRAINT constraint_name PRIMARY KEY (column1, column2, ... column_n);
sqlplus ALTER TABLE table_name add CONSTRAINT constraint_name PRIMARY KEY (id);
dba 中,右击表名,选择“察看/编辑详细资料” 就可以了建立序列号:
create sequence ZSF_ID
minvalue 1
maxvalue 9999
start with 1
increment by 1
cache 20或者在pl/sql中点击Sequence,选择new就可以可视化建立
CREATE TABLE EMPLOYEE
(
ID NUMBER (5,0) ,
EMPLOYEEID VARCHAR2 (20) ,
EMPLOYEESEX NUMBER (1,0),
EMPLOYEEAGE NUMBER (3,0),
.....
);
--建主键
ALTER TABLE EMPLOYEE ADD PRIMARY KEY (ID) ;--定义ID为主键--建序列
CREATE SEQUENCE EMPLOYEE_S INCREMENT BY 1 START WITH 1;--从1开始编号,增量为1
--建触发器自动给ID赋值
CREATE OR REPLACE TRIGGER EMPLOYEE_BIR_T
BEFORE INSERT
ON EMPLOYEE FOR EACH ROW
BEGIN
SELECT EMPLOYEE_S.NEXTVAL INTO :NEW.ID FROM DUAL;
END;
/
ALTER TABLE EMPLOYEE ADD CONSTRAINT PK_EMPLOYEE_ID PRIMARY KEY (ID) ;--定义ID为主键
或者直接在建表时直接指定:--建表
CREATE TABLE EMPLOYEE
(
ID NUMBER (5,0) PRIMARY KEY,
EMPLOYEEID VARCHAR2 (20) ,
EMPLOYEESEX NUMBER (1,0),
EMPLOYEEAGE NUMBER (3,0),
.....
);