Oracle数据库中创建自增主键的实例教程_oracle_

 Create Table Student( id number(12) primary key, --通过序列和触发器实现id的自增 name varchar2(20) , age number(3) , sex number(1) ) 

 Create Sequence SEQ_STUDENT minvalue 1 maxvalue 99999999999999999999 start with 1 --从1开始 increment by 1 --增量为1 cache 0 order; 

 Create or Replace Trigger STUDENT_AUTOINCREMENT Before Insert on Student For Each Row When (NEW.ID IS NULL) Begin Select SEQ_STUDENT.NEXTVAL INTO :NEW.ID FROM DUAL; End; 

 SELECT * FROM DAYSBFJ.DAYS_CARD_UPDATE3 order by id asc --alter table DAYSBFJ.DAYS_CARD_UPDATE3 add source_Flag varchar2(2); --create sequence DAYS_CARD_UPDATE2_SEQ_ID minvalue 1 maxvalue 999999999 start with 1; --Update DAYSBFJ.DAYS_CARD_UPDATE2 set id = DAYS_CARD_UPDATE2_SEQ_ID.nextval; --update DAYSBFJ.DAYS_CARD_UPDATE3 set SOURCE_FLAG = '2' 

 create table test1(name1 varchar2(40),city varchar2(40)); 

 insert into test1 values('name1','nanjing'); insert into test1 values('name1','nanjing'); insert into test1 values('name2','nanjing1'); insert into test1 values('name3','nanjing2'); insert into test1 values('name4','nanjing3'); insert into test1 values('name5','nanjing4'); insert into test1 values('name6','nanjing5'); insert into test1 values('name7','nanjing6'); insert into test1 values('name8','nanjing7'); insert into test1 values('name9','nanjing8'); insert into test1 values('name10','nanjing9'); insert into test1 values('name10','nanjing9'); insert into test1 values('name12','nanjing11'); insert into test1 values('name13','nanjing12'); insert into test1 values('name14','nanjing13'); commit; 

 alter table TEST1 add id number(10); 

 create sequence SEQ_ID minvalue 1 maxvalue 999999999 start with 1; 

 Update test1 set id=seq_id.nextval; commit; 

 alter table TEST1 add constraint PK_TEST1 primary key (ID); select ID,Name1,CITY from TEST1;