/*    数据的更新        增加        删除        修改*/-----------------------------------增加(一次只能插入一条数据)--自定义插入数据列的顺序INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(8888,‘DFBB‘,2666,10);--按照数据库默认的顺序插入INSERT INTO EMP VALUES(9999,‘RWX‘,‘JIAOZHU‘,7788,SYSDATE,3333,NULL,10);--插入查询的结果INSERT INTO EMP(EMPNO,ENAME) SELECT DEPTNO,DNAME FROM DEPT; CREATE TABLE EMPCOPY AS SELECT * FROM EMP WHERE 1=2;--SQL注入(将来写代码的时候要防止sql注入)SELECT * FROM EMP WHERE JOB = ‘CLERK‘ OR 1 = 1;--错误的示范INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(8888,‘DFBB‘,2666);INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(8888,‘DFBB‘,2666,10,2);INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(‘abcd‘,‘DFBB‘,2666,10);INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(56789,‘DFBB‘,2666,10);INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(‘1234‘,‘DFBB‘,2666,10);INSERT INTO EMP(EMPNO,ENAME,SAL,DEPTNO) VALUES(567,‘DFBB‘,2666,10);-----------------------------------删除DELETE FROM EMP;DELETE FROM EMP WHERE EMPNO = ‘7788‘;DELETE FROM EMP WHERE ENAME LIKE ‘%S%‘ AND SAL>2000;--有毒 慎用CREATE TABLE EMPCOPY AS SELECT * FROM EMPTRUNCATE TABLE EMPCOPY;-----------------------------------修改UPDATE EMP SET SAL = SAL+1000 ,COMM = 800,JOB = ‘CODER‘;UPDATE EMP SET SAL = SAL*1.2 WHERE EMPNO = 7788;UPDATE EMP SET SAL = SAL*1.2 WHERE ENAME LIKE ‘%A%‘ AND SAL<2000;ROLLBACK;