Oracle - 数据更新 - 增删改

Posted 2020-09-20 路迢迢

/*
    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 EMP
TRUNCATE 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;