ORACLE查询语句
Posted 风和日丽2010
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--建表FAMILYINF
CREATE TABLE FAMILYINFO(
FNO NUMBER CONSTRAINT FC001 PRIMARY KEY,--把字段fno约束为主键
FNAME VARCHAR2(20) CONSTRAINT FC002 NOT NULL,--把字段FNAME的约束条件设为“不能为空”
SEX VARCHAR2(20) DEFAULT ‘MALE‘CONSTRAINT FC003 CHECK(SEX IN(‘MALE‘,‘FEMALE‘)),--把字段’SEX‘的约束条件设为’性别默认条件下为’MALE‘，如果自己填写只能填写’MALE‘或’FEMALE‘
FAGE NUMBER,
REL VARCHAR2(20),--家庭成员关系字段
HOBITNO NUMBER CONSTRAINT FC004 REFERENCES HOBITINFO(HNO) ON DELETE SET NULL --约束条件设为，表’HOBITINFO‘中字段’HNo‘的外键，删除引用表中字段时，设为空值
);
--建兴趣表HOBITINF
CREATE TABLE HOBITINFO(
HNO NUMBER CONSTRAINT HC001 PRIMARY KEY, --将‘ HNO’设为主键
HNAME VARCHAR2(20) CONSTRAINT HC002 NOT NULL--将‘HNAME’约束条件设为‘不能为空’
);
--删除表HOBITINFO
DROP TABLE HOBITINFO;
--添加信息
INSERT INTO HOBITINFO VALUES(1,‘MOVIE‘);
INSERT INTO HOBITINFO VALUES(2,‘CG‘);
INSERT INTO HOBITINFO VALUES(3,‘TW‘);
SELECT * FROM HOBITINFO;
DELETE FROM HOBITINFO WHERE HNO=3;
SELECT * FROM FAMILYINFO;
TRUNCATE TABLE FAMILYINFO;
DROP TABLE FAMILYINFO;
INSERT INTO FAMILYINFO VALUES(1,‘PHL‘,‘NAN‘,27,‘FATHER‘);
INSERT INTO FAMILYINFO VALUES(2,‘HYQ‘,‘NAN‘,48,‘MATHER‘);
INSERT INTO FAMILYINFO VALUES(3,‘PQ‘,‘NAN‘,27,‘BROTHER‘);
INSERT INTO FAMILYINFO VALUES(4,‘PC‘,‘NAN‘,20,‘MIN‘);
--DDL ALTER TABLE (修改表)
ALTER TABLE FAMILYINFO RENAME TO PCFAMILY;--将FAMILYINFO的表名重命名为PCFAMILY
ALTER TABLE PCFAMILY ADD(--添加列即字段及其属性
HEIGH VARCHAR2(5)，
SX VARCHAR2(10) CONSTRAINT PC002 NOT NULL--字段SX创建“不能为空”的约束条件
);
ALTER TABLE PCFAMILY MODIFY(--修改字段的属性
HEIGH CHAR(20)
);
ALTER TABLE PCFAMILY DROP COLUMN HEIGH;--删除字段HEIGH
ALTER TABLE PCFAMILY RENAME COLUMN SX TO SX1;--修改约束字段名
ALTER TABLE PCFAMILY DROP COLUMN SX1;--删除约束字段
--DDL 之 DROP TABLE(删除表)
DROP TABLE HOBITINFO CASCADE CONSTRAINTS;
--DDL 之 TRUNCATE TABLE 清空表记录
TRUNCATE TABLE PCFAMILY;
--DML 之 INSERT(插入，添加记录）
INSERT INTO PCFAMILY(FNO,SEX,FNAME,FAGE) VALUES(4,‘NANE‘,‘LIU‘||‘DAYE‘,45+20);--如果指定插入字段顺序，则values里的信息就要对照前面指定的字段填写
INSERT INTO PCFAMILY VALUES();
--学生表
CREATE TABLE STUDENT(
SNO NUMBER CONSTRAINT SC001 PRIMARY KEY,
SNAME VARCHAR2(10) CONSTRAINT SC002 NOT NULL,
SSEX VARCHAR(10) CONSTRAINT S003 CHECK(SSEX IN (‘M‘,‘F‘))
);
--老师表
CREATE TABLE TEACHER(
TNO NUMBER CONSTRAINT TC001 PRIMARY KEY,
TNAME VARCHAR2(10) CONSTRAINT TC002 NOT NULL
);
--课程表
CREATE TABLE COURSE(
CNO NUMBER CONSTRAINT CC001 PRIMARY KEY,
CNAME VARCHAR2(20) CONSTRAINT CC002 NOT NULL,
TNO NUMBER CONSTRAINT CC003 REFERENCES TEACHER(TNO)
);
--成绩表
CREATE TABLE SCORE(
SNO NUMBER CONSTRAINT SSC001 REFERENCES STUDENT(SNO),
CNO NUMBER CONSTRAINT SSC002 REFERENCES COURSE(CNO),
GRADE VARCHAR2(20),
CONSTRAINT SSC003 PRIMARY KEY(SNO,CNO)
);
--查询表是否建立成功已经存在
SELECT * FROM STUDENT;
SELECT * FROM TEACHER;
SELECT * FROM COURSE;
SELECT * FROM SCORE;
--删除表
DROP TABLE STUDENT;
DROP TABLE TEACHER;
DROP TABLE COURSE;
DROP TABLE SCORE;
--向表里添加信息
INSERT INTO STUDENT VALUES(1,‘aaaa‘,‘M‘);
INSERT INTO STUDENT VALUES(2,‘bbbb‘,‘M‘);
INSERT INTO STUDENT VALUES(3,‘cccc‘,‘F‘);
INSERT INTO TEACHER VALUES(1,‘AAAA‘);
INSERT INTO TEACHER VALUES(2,‘BBBB‘);
INSERT INTO TEACHER VALUES(3,‘CCCC‘);
INSERT INTO COURSE VALUES(1,‘yw‘,2);
INSERT INTO COURSE VALUES(2,‘sx‘,3);
INSERT INTO COURSE VALUES(3,‘yy‘,2);
INSERT INTO SCORE VALUES(1,2,89);
INSERT INTO SCORE VALUES(2,3,120);
INSERT INTO SCORE VALUES(3,1,110);
--DML 之UPDATE
UPDATE SCORE SET GRADE=GRADE-1;
UPDATE SCORE SET GRADE=GRADE+1 WHERE SNO=2;
UPDATE SCORE SET GRADE=GRADE+1 WHERE SNO=2 AND CNO=3;
--------------------------------------------------------------------------------------------
-- DQL 之 SELECT
SELECT CHR(107) HAHA FROM DUAL;
SELECT CURRENT_DATE FROM DUAL;
SELECT TRUNC(ABS(MONTHS_BETWEEN(DATE‘1998-08-08‘,CURRENT_DATE)/12)) AGE FROM DUAL;
SELECT SNO AS 学号, SNAME 学生姓名 FROM STUDENT;
SELECT ALL SSEX FROM STUDENT;
SELECT DISTINCT SSEX FROM STUDENT;
SELECT UNIQUE SSEX FROM STUDENT;
SELECT * FROM SCORE WHERE GRADE < 60;
SELECT ROWID,ROWNUM,STUDENT.* FROM STUDENT;
SELECT * FROM STUDENT WHERE ROWNUM = 1;
SELECT * FROM STUDENT WHERE ROWNUM <= 2;
SELECT * FROM (SELECT ROWNUM AS RN,STUDENT.* FROM STUDENT) WHERE RN = 2;
SELECT CNO,AVG(GRADE) FROM SCORE GROUP BY CNO;
SELECT CNO,AVG(GRADE) FROM SCORE GROUP BY CNO HAVING AVG(GRADE) > 80;
SELECT SSEX,COUNT(SNO) FROM STUDENT GROUP BY SSEX;
SELECT SNO FROM SCORE WHERE CNO = ‘C001‘ AND GRADE = (SELECT MAX(GRADE) FROM SCORE WHERE CNO = ‘C001‘);
SELECT SNO FROM SCORE WHERE CNO = ‘C001‘ AND GRADE >= ALL(SELECT GRADE FROM SCORE WHERE CNO = ‘C001‘);
SELECT * FROM SCORE ORDER BY CNO ASC,GRADE DESC;
SELECT * FROM STUDENT,SCORE WHERE STUDENT.SNO = SCORE.SNO;
SELECT SNAME FROM STUDENT,SCORE
WHERE STUDENT.SNO = SCORE.SNO AND CNO = ‘C001‘ AND GRADE = (SELECT MAX(GRADE) FROM SCORE WHERE CNO = ‘C001‘);
SELECT * FROM STUDENT INNER JOIN SCORE ON STUDENT.SNO = SCORE.SNO;
SELECT * FROM STUDENT INNER JOIN SCORE USING(SNO);
SELECT * FROM STUDENT CROSS JOIN SCORE WHERE STUDENT.SNO = SCORE.SNO;
SELECT * FROM STUDENT NATURAL INNER JOIN SCORE;
SELECT * FROM STUDENT LEFT OUTER JOIN SCORE ON STUDENT.SNO = SCORE.SNO;
SELECT * FROM STUDENT RIGHT OUTER JOIN SCORE USING(SNO);
SELECT * FROM STUDENT FULL OUTER JOIN SCORE USING(SNO);
-- 查询考试不及格的学生姓名和挂科的科目名称
SELECT SNAME,CNAME
FROM (SCORE LEFT JOIN STUDENT USING(SNO))
LEFT JOIN COURSE USING(CNO)
WHERE GRADE < 60;
-- 查询所有java考试成绩高于平均分的学生的姓名和成绩
SELECT SNAME,GRADE
FROM (SCORE LEFT JOIN STUDENT USING(SNO))
LEFT JOIN COURSE USING(CNO)
WHERE CNAME = ‘JAVA‘
AND GRADE > (
SELECT AVG(GRADE) FROM SCORE LEFT JOIN COURSE USING(CNO)
WHERE CNAME = ‘JAVA‘
);
select * from (SELECT * from test RIGHT JOIN t_grade using(ID) ) a where `数学` > 90
-- 查询同时参加了C001和C002科目考试的学生编号
SELECT SNO FROM
(SELECT SNO,CNO FROM SCORE WHERE CNO = ‘C001‘)
INNER JOIN
(SELECT SNO,CNO FROM SCORE WHERE CNO = ‘C002‘)
USING(SNO);
-- 查询lili同学参加的所有科目考试中成绩最高的那门科目的授课老师名字
SELECT TNAME,CNAME FROM
TEACHER LEFT JOIN COURSE USING(TNO)
WHERE CNO IN (
SELECT CNO FROM
SCORE LEFT JOIN STUDENT USING(SNO)
WHERE SNAME = ‘LILI‘
AND GRADE = ( SELECT MAX(GRADE) FROM
SCORE LEFT JOIN STUDENT USING(SNO)
WHERE SNAME = ‘LILI‘
)
);
-- 查询库存目前还有多少
CREATE TABLE CLOTHER_STORE(
CTYPE VARCHAR2(10),
STORENUM NUMBER
);
CREATE TABLE CLOTHER_SALE(
CTYPE VARCHAR2(10),
SALENUM NUMBER
);
INSERT INTO CLOTHER_STORE VALUES(‘T-SHIRT‘,600);
INSERT INTO CLOTHER_STORE VALUES(‘COAT‘,700);
INSERT INTO CLOTHER_SALE VALUES(‘T-SHIRT‘,140);
INSERT INTO CLOTHER_SALE VALUES(‘T-SHIRT‘,165);
INSERT INTO CLOTHER_SALE VALUES(‘COAT‘,90);
INSERT INTO CLOTHER_SALE VALUES(‘COAT‘,78);
SELECT CTYPE,STORENUM-SNUM AS KCSY FROM
CLOTHER_STORE LEFT JOIN
(SELECT CTYPE,SUM(SALENUM) SNUM FROM CLOTHER_SALE GROUP BY CTYPE)
USING(CTYPE);
-- 切换到scott用户
SELECT * FROM EMP;
SELECT * FROM DEPT;
--1． 列出至少有一个员工的所有部门。
SELECT DISTINCT DEPTNO,DNAME FROM
EMP LEFT JOIN DEPT USING(DEPTNO);
--2． 列出薪金比"SMITH"多的所有员工。
SELECT * FROM EMP WHERE SAL > (SELECT SAL FROM EMP WHERE ENAME = ‘SMITH‘);
--3． 列出所有员工的姓名及其直接上级的姓名。
SELECT E.ENAME 员工姓名,B.ENAME 上级姓名 FROM
EMP E LEFT JOIN EMP B ON E.MGR = B.EMPNO;
--4． 列出受雇日期早于其直接上级的所有员工。
SELECT E.ENAME 员工姓名,E.HIREDATE 员工受雇日期,B.ENAME 上级姓名,B.HIREDATE 上级受雇日期
FROM EMP E LEFT JOIN EMP B ON E.MGR = B.EMPNO
WHERE E.HIREDATE < B.HIREDATE;
--5． 列出部门名称和这些部门的员工信息，同时列出那些没有员工的部门。
SELECT DNAME,EMP.* FROM EMP RIGHT JOIN DEPT ON EMP.DEPTNO = DEPT.DEPTNO;
--6． 列出所有"CLERK"（办事员）的姓名及其部门名称。
SELECT ENAME,DNAME FROM EMP LEFT JOIN DEPT USING(DEPTNO) WHERE JOB = ‘CLERK‘;
--7． 列出最低薪金大于1500的各种工作。
SELECT JOB FROM EMP GROUP BY JOB HAVING MIN(SAL) > 1500;
--8． 列出在部门"SALES"（销售部）工作的员工的姓名，假定不知道销售部的部门编号。
SELECT ENAME FROM EMP LEFT JOIN DEPT USING(DEPTNO) WHERE DNAME = ‘SALES‘;
--9． 列出薪金高于公司平均薪金的所有员工。
SELECT * FROM EMP WHERE SAL > (SELECT AVG(SAL) FROM EMP);
--10．列出与"SCOTT"从事相同工作的所有员工。
SELECT * FROM EMP WHERE JOB = (SELECT JOB FROM EMP WHERE ENAME = ‘SCOTT‘) AND ENAME <> ‘SCOTT‘;
--11．列出薪金等于部门30中员工的薪金的所有员工的姓名和薪金。
SELECT ENAME,SAL FROM EMP WHERE SAL = ANY(SELECT SAL FROM EMP WHERE DEPTNO = 30) AND DEPTNO <> 30;
--12．列出薪金高于在部门30工作的所有员工的薪金的员工姓名和薪金。
SELECT ENAME,SAL FROM EMP WHERE SAL > ALL(SELECT SAL FROM EMP WHERE DEPTNO = 30) AND DEPTNO <> 30;
--13．列出在每个部门工作的员工数量、平均工资和平均服务期限。
SELECT DEPTNO,COUNT(EMPNO) 员工数量,ROUND(AVG(SAL),2) 平均工资,
ROUND(AVG(MONTHS_BETWEEN(CURRENT_DATE,HIREDATE))/12,2) 平均服务年限
FROM EMP RIGHT JOIN DEPT USING(DEPTNO)
GROUP BY DEPTNO;
--14．列出所有员工的姓名、部门名称和工资。
SELECT ENAME,DNAME,SAL FROM EMP LEFT JOIN DEPT USING(DEPTNO);
--15．列出所有部门的详细信息和部门人数。
SELECT DEPT.DEPTNO,DNAME,LOC,COUNT(EMPNO) FROM
DEPT LEFT JOIN EMP ON EMP.DEPTNO = DEPT.DEPTNO
GROUP BY DEPT.DEPTNO,DNAME,LOC;
--16．列出各种工作的最低工资。
SELECT JOB,MIN(SAL) FROM EMP GROUP BY JOB;
--17．列出各个部门的MANAGER（经理）的最低薪金。
SELECT MIN(SAL) FROM EMP WHERE JOB = ‘MANAGER‘;
--18．列出所有员工的年工资,按年薪从低到高排序。
SELECT ENAME,SAL*12+NVL(COMM,0) 年薪 FROM EMP ORDER BY 年薪;
--19．列出经理人的名字。
SELECT ENAME FROM EMP WHERE JOB = ‘MANAGER‘ OR JOB = ‘PRESIDENT‘;
--20．不用组函数，求出薪水的最大值。
SELECT SAL FROM (SELECT SAL FROM EMP ORDER BY SAL DESC) WHERE ROWNUM = 1;
--21．列出薪资第2高到第8高的员工。
SELECT SAL FROM(
SELECT ROWNUM RN,SAL FROM
(SELECT SAL FROM EMP ORDER BY SAL DESC))
WHERE RN >= 2 AND RN <= 8;
-- 切换回普通用户
-- union, INTERSECT,MINUS
CREATE TABLE A1 (
V1 NUMBER,
V2 VARCHAR2(10)
);
CREATE TABLE A2 (
V3 NUMBER,
V4 VARCHAR2(10),
V5 VARCHAR2(10)
);
INSERT INTO A1 VALUES(10,‘A001‘);
INSERT INTO A1 VALUES(11,‘A002‘);
INSERT INTO A2 VALUES(10,‘A001‘,‘HAHA‘);
INSERT INTO A2 VALUES(12,‘A003‘,‘HEIHEI‘);
INSERT INTO A2 VALUES(13,‘A004‘,‘HOHO‘);
SELECT * FROM A1 UNION (SELECT V3，V4 FROM A2);
SELECT * FROM A1 UNION ALL (SELECT V3，V4 FROM A2);
SELECT * FROM A1 INTERSECT (SELECT V3，V4 FROM A2);
SELECT * FROM A1 MINUS (SELECT V3，V4 FROM A2);
-- 带锁查询
UPDATE CLOTHER_STORE SET STORENUM = 600 WHERE CTYPE = ‘T-SHIRT‘;
SELECT * FROM CLOTHER_STORE FOR UPDATE WAIT 5;
UPDATE CLOTHER_STORE SET STORENUM = STORENUM - 400 WHERE CTYPE = ‘T-SHIRT‘;
-- DCL 之 COMMIT
SELECT * FROM STUDENT;
DELETE FROM STUDENT WHERE SNO = ‘S011‘;
COMMIT;
-- DCL 之 ROLLBACK 和 SAVEPOINT
SELECT * FROM CLOTHER_SALE;
UPDATE CLOTHER_SALE SET SALENUM = SALENUM + 10;
ROLLBACK;
UPDATE CLOTHER_SALE SET SALENUM = SALENUM + 10;
SAVEPOINT CPD;
UPDATE CLOTHER_SALE SET SALENUM = SALENUM + 10;
ROLLBACK TO SAVEPOINT CPD;
-- DCL 之 GRANT
GRANT CREATE VIEW TO LUYY124;
GRANT UPDATE ANY TABLE TO LUYY124;
-- DDL 之 REVOKE
REVOKE CREATE VIEW FROM LUYY124;
-- CREATE VIEW
CREATE OR REPLACE VIEW STUDENT_VIEW AS
SELECT * FROM (STUDENT LEFT JOIN SCORE USING(SNO)) LEFT JOIN COURSE USING(CNO);
SELECT * FROM STUDENT_VIEW;
SELECT SNAME,CNAME FROM STUDENT_VIEW WHERE GRADE < 60;
SELECT * FROM SCORE;
UPDATE SCORE SET GRADE = GRADE + 1 WHERE SNO = ‘S001‘ AND CNO = ‘C001‘;
CREATE OR REPLACE VIEW STUDENT_VIEW AS SELECT * FROM SCORE;
UPDATE STUDENT_VIEW SET GRADE = GRADE - 1 WHERE SNO = ‘S001‘ AND CNO = ‘C001‘;
-- CREATE INDEX
CREATE INDEX SNAME_INDEX ON STUDENT(SNAME ASC) ;
SELECT * FROM STUDENT WHERE SNAME = ‘LILI‘;
DROP INDEX SNAME_INDEX;
-- PLSQL
-- 匿名块
SELECT * FROM STUDENT;
DECLARE
V_SNO VARCHAR2(4) := ‘S011‘;
V_SNAME VARCHAR(20) := ‘FANGYUQIN‘;
V_SSEX VARCHAR2(1) := ‘F‘;
BEGIN
INSERT INTO STUDENT VALUES(V_SNO, V_SNAME, V_SSEX);
DBMS_OUTPUT.put_line(‘插入成功‘);
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.put_line(SQLERRM);
END;
DECLARE
V_SNO VARCHAR2(4) := ‘S012‘;
V_SNAME VARCHAR2(20);
BEGIN
SELECT SNAME INTO V_SNAME FROM STUDENT WHERE SNO = V_SNO;
DBMS_OUTPUT.put_line(V_SNAME);
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.put_line(SQLERRM);
END;
-- 练习：
CREATE TABLE FAKEDATA(
SNO VARCHAR2(4),
SNAME VARCHAR2(10)
);
SELECT * FROM FAKEDATA;
DECLARE
SNO_PREFIX VARCHAR2(1) := ‘S‘;
SNAME_PREFIX VARCHAR2(4) := ‘LUYY‘;
SUFIX VARCHAR2(3);
I NUMBER;
BEGIN
FOR I IN 1..100
LOOP
IF I < 10 THEN
SUFIX := ‘00‘ || I;
ELSIF I < 100 THEN
SUFIX := ‘0‘ || I;
ELSE
SUFIX := ‘‘ || I;
END IF;
INSERT INTO FAKEDATA VALUES(SNO_PREFIX || SUFIX, SNAME_PREFIX || SUFIX);
END LOOP;
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.put_line(SQLERRM);
END;
-- 记录类型 RECORD
DECLARE
TYPE STUDENTRECORD IS RECORD(
V_SNO STUDENT.SNO%TYPE,
V_SNAME STUDENT.SNAME%TYPE,
V_SSEX STUDENT.SSEX%TYPE
);
SR STUDENTRECORD;
BEGIN
SELECT * INTO SR FROM STUDENT WHERE SNO = ‘S010‘;
DBMS_OUTPUT.put_line(SR.V_SNO||‘: ‘||SR.V_SNAME);
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.put_line(SQLERRM);
END;
DECLARE
SR STUDENT%ROWTYPE;
BEGIN
SELECT * INTO SR FROM STUDENT WHERE SNO = ‘S010‘;
DBMS_OUTPUT.put_line(SR.SNO||‘: ‘||SR.SNAME);
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.put_line(SQLERRM);
END;
-- 带名块
-- PROCEDURE
CREATE OR REPLACE PROCEDURE P1(
V_SNO IN VARCHAR2,
V_SNAME OUT VARCHAR2
)
IS
BEGIN
SELECT SNAME INTO V_SNAME FROM STUDENT WHERE SNO = V_SNO;
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.put_line(SQLERRM);
END P1;
DECLARE
V1 VARCHAR2(4) := ‘S003‘;
V2 VARCHAR2(20);
BEGIN
P1(V1,V2);
DBMS_OUTPUT.put_line(V2);
END;
DROP PROCEDURE P1;
-- FUNCTION
CREATE OR REPLACE FUNCTION F1(
V_CNAME IN VARCHAR2
)
RETURN VARCHAR2
IS
V_TNAME VARCHAR2(20);
BEGIN
SELECT TNAME INTO V_TNAME FROM COURSE LEFT JOIN TEACHER USING(TNO) WHERE CNAME = V_CNAME;
RETURN V_TNAME;
END F1;
DECLARE
V1 VARCHAR2(10) := ‘JAVA‘;
V2 VARCHAR2(20);
BEGIN
V2 := F1(V1);
DBMS_OUTPUT.put_line(V2);
END;
SELECT F1(‘RJZL‘) FROM DUAL;
DROP FUNCTION F1;
-- 游标 CURSOR
DECLARE
CURSOR MYCURSOR(V_SNO VARCHAR2) IS
SELECT * FROM SCORE WHERE SNO = V_SNO;
SR SCORE%ROWTYPE;
BEGIN
IF MYCURSOR%ISOPEN = FALSE THEN
OPEN MYCURSOR(‘S002‘);
END IF;
LOOP
FETCH MYCURSOR INTO SR;
EXIT WHEN MYCURSOR%NOTFOUND;
DBMS_OUTPUT.put_line(SR.CNO||‘: ‘||SR.GRADE);
END LOOP;
DBMS_OUTPUT.put_line(‘共计‘||MYCURSOR%ROWCOUNT||‘条记录‘);
CLOSE MYCURSOR;
END;
-- 触发器 TRIGGER
CREATE TABLE MEMBERINFO(
MID VARCHAR2(4) CONSTRAINT MC001 PRIMARY KEY,
QCOIN NUMBER(10)
);
CREATE TABLE RECHARGE(
RNO VARCHAR2(4) CONSTRAINT RC001 PRIMARY KEY,
MID VARCHAR2(4) CONSTRAINT RC002 REFERENCES MEMBERINFO(MID),
REQCOIN NUMBER(10)
);
CREATE TABLE CONSUME(
CNO VARCHAR2(4) CONSTRAINT CC001 PRIMARY KEY,
MID VARCHAR2(4) CONSTRAINT CC002 REFERENCES MEMBERINFO(MID),
CQCOIN NUMBER(10)
);
INSERT INTO MEMBERINFO VALUES(‘M001‘,400);
INSERT INTO MEMBERINFO VALUES(‘M002‘,700);
INSERT INTO MEMBERINFO VALUES(‘M003‘,1400);
SELECT * FROM MEMBERINFO;
SELECT * FROM RECHARGE;
SELECT * FROM CONSUME;
CREATE OR REPLACE TRIGGER RECHARGE_INSERT
AFTER INSERT
ON RECHARGE
FOR EACH ROW
BEGIN
UPDATE MEMBERINFO SET QCOIN = QCOIN + :NEW.REQCOIN WHERE MID = :NEW.MID;
END RECHARGE_INSERT;
CREATE OR REPLACE TRIGGER CONSUME_INSERT
BEFORE INSERT
ON CONSUME
FOR EACH ROW
DECLARE
V_QCOIN NUMBER(10);
BEGIN
SELECT QCOIN INTO V_QCOIN FROM MEMBERINFO WHERE MID = :NEW.MID;
IF V_QCOIN >= :NEW.CQCOIN THEN
UPDATE MEMBERINFO SET QCOIN = QCOIN - :NEW.CQCOIN WHERE MID = :NEW.MID;
ELSE
RAISE_APPLICATION_ERROR(-20001,‘余额不足‘);
END IF;
END CONSUME_INSERT;
INSERT INTO RECHARGE VALUES(‘R001‘,‘M002‘,500);
INSERT INTO CONSUME VALUES(‘C002‘,‘M002‘,200);
INSERT INTO CONSUME VALUES(‘C003‘,‘M003‘,2000);
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