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  • Oracle

    /*
        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;
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  • 原文地址:https://www.cnblogs.com/chenglc/p/6922981.html
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