ORcale 自增列 实例

CREATE TABLE  e
    (
      emp_id CHAR(3),
      emp_name VARCHAR(20),
      emp_sal varchar(20)
    )
   
   
    CREATE TABLE e_temp
    AS
    SELECT * FROM e;
    
     
    CREATE TRIGGER tri_ew
    BEFORE INSERT ON e FOR EACH ROW
    BEGIN
          INSERT INTO e_temp(emp_id,emp_name,emp_sal
          ) VALUES(:NEW.emp_id,:NEW.emp_name,:NEW.emp_sal);
    END;
    
    CREATE TABLE aa
    (
      aa_id CHAR(3),
      sex VARCHAR(10),
      CONSTRAINT pk_aa_id  PRIMARY KEY(aa_id)
    )
   
    CREATE SEQUENCE aa_sequ
            INCREMENT BY 1
            START WITH 1
            MAXVALUE 100
     MINVALUE 1
     NOCYCLE;
  
   CREATE  TRIGGER aa_t
   BEFORE INSERT ON aa FOR EACH ROW
   BEGIN
         SELECT aa_sequ.nextval
         INTO :NEW.aa_id
         FROM dual;
   END;