创建数据库 1 2 3 4 CREATE TABLE STUDENT(ID NUMBER PRIMARY KEY, NAME VARCHAR(200) NOT NULL, SEX VARCHAR(200), CREATE_DATE DATE); 指定表名注释 1 COMMENT ON TABLE STUDENT IS '学生表'; 指定列注释 1 2 3 4 COMMENT ON COLUMN STUDENT.ID IS '学生ID'; COMMENT ON COLUMN STUDENT.NAME IS '学生姓名'; COMMENT ON COLUMN STUDENT.SEX IS '学生性别'; COMMENT ON COLUMN STUDENT.CREATE_DATE IS '创建日期'; 创建序列 1 2 3 4 5 6 CREATE SEQUENCE student_seq INCREMENT BY 1 -- 每次增加1个 START WITH 1 --从1开始计数 NOMAXVALUE -- 不设置最大值 NOCYCLE --直累加,不循环 NOCACHE --不建立缓冲区 创建触发器 1 2 3 4 5 6 CREATE OR REPLACE TRIGGER STUDENT_TRG BEFORE INSERT ON STUDENT FOR EACH ROW -- WHEN (new.ID is null) 设置主键存在时,不触发触发器 BEGIN SELECT STUDENT_SEQ.NEXTVAL INTO :NEW.ID FROM DUAL; END;