TO_DATE('2004-9-6','YYYY-MM-DD'), 2700,1200,NULL,NULL,NULL,NULL); INSERT INTO EMPLOYEE VALUES('08','AA',TO_DATE('2004-9-6','YYYY-MM-DD'), 2700,1200,NULL,NULL,NULL,NULL); INSERT INTO EMPLOYEE VALUES('09','BB',TO_DATE('2004-9-6','YYYY-MM-DD'), 2700,1200,NULL,NULL,NULL,NULL); INSERT INTO EMPLOYEE VALUES('10','aa',TO_DATE('2004-9-6','YYYY-MM-DD'), 2700,1200,NULL,NULL,NULL,NULL); ----SELECT * FROM EMPLOYEE; ---DELETE以下为删除元组,也就是一组 DELETE FROM EMPLOYEE EMP WHERE EMP.EMPLOYEEID = '02'; ---UPDATE EMPLOYEE UPDATE EMPLOYEE SET MANAGERID = '01';--更改一列上所有的数据 UPDATE EMPLOYEE SET COMMISSION = 850 WHERE EMPLOYEEID = '02'; --DELETE POSTION DELETE POSITION;--删除所有的记录 DELETE POSITION WHERE POSITIONNAME='程序员'; ---SELECT EMPLOYEE SELECT * FROM EMPLOYEE; SELECT EMP.EMPLOYEEID ID,EMP.NAME 姓名 FROM EMPLOYEE EMP;--指定别名 SELECT EMP.EMPLOYEEID ,EMP.NAME FROM EMPLOYEE EMP WHERE EMP.NAME = '张五'; ---DISTINCT 要在SELECT后 --可以看到张五只有一条记录了 SELECT DISTINCT EMP.NAME 姓名, EMP.SALARY 薪水 FROM EMPLOYEE EMP; ---||串联 将多列作为一列 SELECT EMP.NAME || ' 的月薪是 ' || EMP.SALARY INFO FROM EMPLOYEE EMP; ---算术表达式 SELECT EMP.NAME, EMP.SALARY * 12 年薪 FROM EMPLOYEE EMP; ---WHERE 子句 ----> SELECT EMP.NAME,EMP.SALARY FROM EMPLOYEE EMP WHERE EMP.SALARY > 1600; ---BETWEEN AND SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY FROM EMPLOYEE EMP WHERE EMP.SALARY BETWEEN 1600 AND 2500; ----NOT BETWEEN AND SELECT EMP.NAME,EMP.SALARY FROM EMPLOYEE EMP WHERE EMP.SALARY NOT BETWEEN 1600 AND 2500; ----IN SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY FROM EMPLOYEE EMP WHERE EMP.SALARY IN(1600,2001,2004); ---NOT IN SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY FROM EMPLOYEE EMP WHERE EMP.SALARY NOT IN(1600,2003); ----IS NULL UPDATE EMPLOYEE SET MANAGERID = NULL WHERE EMPLOYEE.EMPLOYEEID = '01'; SELECT * FROM EMPLOYEE EMP WHERE EMP.MANAGERID IS NULL; --- IS NOT NULL SELECT * FROM EMPLOYEE EMP WHERE EMP.MANAGERID IS NOT NULL; ---LIKE --SELECT * FROM EMPLOYEE; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME LIKE '%刚'; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME LIKE '_刚'; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME LIKE '%刚%'; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME LIKE '_刚_'; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME LIKE '%刚_'; ---NOT LIKE SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME NOT LIKE '%刚%'; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME NOT LIKE '%刚'; SELECT * FROM EMPLOYEE EMP WHERE EMP.NAME NOT LIKE '%刚_'; ---AND SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY,EMP.COMMISSION FROM EMPLOYEE EMP WHERE EMP.SALARY >1600 AND EMP.COMMISSION >=1500; ---OR SELECT FROM EMPLOYEE EMP WHERE EMP.EMPLOYEEID = '02'OR EMP.NAME = '刚果'; ---ORDER BY SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY,EMP.COMMISSION FROM EMPLOYEE EMP ORDER BY SALARY; SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY,EMP.COMMISSION FROM EMPLOYEE EMP ORDER BY EMP.SALARY ,EMP.COMMISSION DESC; ---CASE 子句 --SELECT * FROM EMPLOYEE; SELECT EMP.EMPLOYEEID,EMP.NAME,EMP.SALARY, CASE WHEN EMP.EMPLOYEEID = '02' THEN EMP.SALARY + 400 WHEN EMP.EMPLOYEEID = '03' THEN EMP.SALARY + 7 ELSE EMP.SALARY END 加薪后 FROM EMPLOYEE EMP UPDATE EMPLOYEE EMP SET EMP.SALARY = CASE WHEN EMP.EMPLOYEEID = '02' THEN EMP.SALARY + 400 WHEN EMP.EMPLOYEEID = '03' THEN EMP.SALARY + 7 |