Oracle PL/SQL/Result Set/Minus
Содержание
- 1 All locations, where courses are offering, have no departments
- 2 An MINUS query that uses an ORDER BY clause
- 3 Minus id column
- 4 MINUS: returns all those records from the first query, but not the second
- 5 minus with like operator
- 6 One result set "minus" another result set
- 7 Understanding Intersections and Differences
- 8 Use COUNT to count the rows from a subquery with set operator
All locations, where courses are offering, have no departments
<source lang="sql">
SQL> create table departments
2 ( deptno NUMBER(2) constraint D_PK 3 primary key 4 , dname VARCHAR2(10) 5 , location VARCHAR2(8) 6 , mgr NUMBER(4) 7 ) ;
Table created. SQL> SQL> insert into departments values (10,"ACCOUNTING","NEW YORK",7); 1 row created. SQL> insert into departments values (20,"TRAINING", "DALLAS", 4); 1 row created. SQL> insert into departments values (30,"SALES", "CHICAGO", 6); 1 row created. SQL> insert into departments values (40,"HR", "BOSTON", 9); 1 row created. SQL> create table offerings
2 ( course VARCHAR2(6) 3 , begindate DATE 4 , trainer NUMBER(4) 5 , location VARCHAR2(8) 6 ) ;
Table created. SQL> insert into offerings values ("SQL",date "2009-04-12",13,"DALLAS" ); 1 row created. SQL> insert into offerings values ("OAU",date "2009-08-10",4,"CHICAGO"); 1 row created. SQL> insert into offerings values ("SQL",date "2009-10-04",1,"SEATTLE"); 1 row created. SQL> insert into offerings values ("SQL",date "2009-12-13",1,"DALLAS" ); 1 row created. SQL> insert into offerings values ("JAV",date "2009-12-13",4,"SEATTLE"); 1 row created. SQL> insert into offerings values ("XML",date "2000-02-03",1,"DALLAS" ); 1 row created. SQL> insert into offerings values ("JAV",date "2000-02-01",11,"DALLAS" ); 1 row created. SQL> insert into offerings values ("PLS",date "2000-09-11",8,"DALLAS" ); 1 row created. SQL> insert into offerings values ("XML",date "2000-09-18",NULL,"SEATTLE"); 1 row created. SQL> insert into offerings values ("OAU",date "2000-09-27",13,"DALLAS" ); 1 row created. SQL> insert into offerings values ("ERM",date "2001-01-15",NULL, NULL ); 1 row created. SQL> insert into offerings values ("PRO",date "2001-02-19",NULL,"DALLAS" ); 1 row created. SQL> insert into offerings values ("RSD",date "2001-02-24",8,"CHICAGO"); 1 row created. SQL> SQL> select o.location from offerings o
2 minus 3 select d.location from departments d;
LOCATION
SEATTLE
SQL> SQL> SQL> drop table offerings; Table dropped. SQL> drop table departments; Table dropped. SQL>
</source>
An MINUS query that uses an ORDER BY clause
<source lang="sql">
SQL> CREATE TABLE EMP (EMPNO NUMBER(4) NOT NULL,
2 ENAME VARCHAR2(10), 3 JOB VARCHAR2(9), 4 MGR NUMBER(4), 5 HIREDATE DATE, 6 SAL NUMBER(7, 2), 7 COMM NUMBER(7, 2), 8 DEPTNO NUMBER(2));
SQL> SQL> INSERT INTO EMP VALUES (7369, "SMITH", "CLERK", 7902, TO_DATE("17-DEC-1980", "DD-MON-YYYY"), 800, NULL, 20); SQL> INSERT INTO EMP VALUES (7499, "ALLEN", "SALESMAN", 7698, TO_DATE("20-FEB-1981", "DD-MON-YYYY"), 1600, 300, 30); SQL> INSERT INTO EMP VALUES (7521, "WARD", "SALESMAN", 7698, TO_DATE("22-FEB-1981", "DD-MON-YYYY"), 1250, 500, 30); SQL> INSERT INTO EMP VALUES (7566, "JONES", "MANAGER", 7839, TO_DATE("2-APR-1981", "DD-MON-YYYY"), 2975, NULL, 20); SQL> INSERT INTO EMP VALUES (7654, "MARTIN", "SALESMAN", 7698,TO_DATE("28-SEP-1981", "DD-MON-YYYY"), 1250, 1400, 30); SQL> INSERT INTO EMP VALUES (7698, "BLAKE", "MANAGER", 7839,TO_DATE("1-MAY-1981", "DD-MON-YYYY"), 2850, NULL, 30); SQL> INSERT INTO EMP VALUES (7782, "CLARK", "MANAGER", 7839,TO_DATE("9-JUN-1981", "DD-MON-YYYY"), 2450, NULL, 10); SQL> INSERT INTO EMP VALUES (7788, "SCOTT", "ANALYST", 7566,TO_DATE("09-DEC-1982", "DD-MON-YYYY"), 3000, NULL, 20); SQL> INSERT INTO EMP VALUES (7839, "KING", "PRESIDENT", NULL,TO_DATE("17-NOV-1981", "DD-MON-YYYY"), 5000, NULL, 10); SQL> INSERT INTO EMP VALUES (7844, "TURNER", "SALESMAN", 7698,TO_DATE("8-SEP-1981", "DD-MON-YYYY"), 1500, 0, 30); SQL> INSERT INTO EMP VALUES (7876, "ADAMS", "CLERK", 7788,TO_DATE("12-JAN-1983", "DD-MON-YYYY"), 1100, NULL, 20); SQL> INSERT INTO EMP VALUES (7900, "JAMES", "CLERK", 7698,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 950, NULL, 30); SQL> INSERT INTO EMP VALUES (7902, "FORD", "ANALYST", 7566,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 3000, NULL, 20); SQL> INSERT INTO EMP VALUES (7934, "MILLER", "CLERK", 7782,TO_DATE("23-JAN-1982", "DD-MON-YYYY"), 1300, NULL, 10); SQL> SQL> SQL> select * from emp;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- --------- ---------- --------- ---------- ---------- ----------
7369 SMITH CLERK 7902 17-DEC-80 800 20
7499 ALLEN SALESMAN 7698 20-FEB-81 1600 300 30
7521 WARD SALESMAN 7698 22-FEB-81 1250 500 30
7566 JONES MANAGER 7839 02-APR-81 2975 20
7654 MARTIN SALESMAN 7698 28-SEP-81 1250 1400 30
7698 BLAKE MANAGER 7839 01-MAY-81 2850 30
7782 CLARK MANAGER 7839 09-JUN-81 2450 10
7788 SCOTT ANALYST 7566 09-DEC-82 3000 20
7839 KING PRESIDENT 17-NOV-81 5000 10
7844 TURNER SALESMAN 7698 08-SEP-81 1500 0 30
7876 ADAMS CLERK 7788 12-JAN-83 1100 20
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- --------- ---------- --------- ---------- ---------- ----------
7900 JAMES CLERK 7698 03-DEC-81 950 30
7902 FORD ANALYST 7566 03-DEC-81 3000 20
7934 MILLER CLERK 7782 23-JAN-82 1300 10
SQL> SQL> -- With ORDER BY Clause SQL> SQL> -- An MINUS query that uses an ORDER BY clause: SQL> SQL> select empno, ename
2 from emp
3 where sal > 1000
4 MINUS
5 select empno, ename
6 from emp
7 where sal > 2000
8 ORDER BY 2;
EMPNO ENAME
----------
7876 ADAMS
7499 ALLEN
7654 MARTIN
7934 MILLER
7844 TURNER
7521 WARD
SQL> SQL> drop table emp; SQL> SQL> SQL> SQL> SQL>
</source>
Minus id column
<source lang="sql">
SQL> SQL> CREATE TABLE emp (
2 emp_id NUMBER, 3 ename VARCHAR2(40), 4 hire_date DATE DEFAULT sysdate, 5 end_date DATE, 6 rate NUMBER(5,2), 7 CONSTRAINT emp_pk PRIMARY KEY (emp_id) 8 );
Table created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (101, "Mary", to_date("15-Nov-1961","dd-mon-yyyy"),null,169); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (102, "Tom", to_date("16-Sep-1964","dd-mon-yyyy"),to_date("5-May-2004","dd-mon-yyyy"),135); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (104, "Peter", to_date("29-Dec-1987","dd-mon-yyyy"),to_date("1-Apr-2004","dd-mon-yyyy"),99); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (105, "Mike", to_date("15-Jun-2004","dd-mon-yyyy"),null,121); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (107, "Less", to_date("2-Jan-2004","dd-mon-yyyy"),null,45); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (108, "Park", to_date("1-Mar-1994","dd-mon-yyyy"),to_date("15-Nov-2004","dd-mon-yyyy"),220); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (110, "Ink", to_date("4-Apr-2004","dd-mon-yyyy"),to_date("30-Sep-2004","dd-mon-yyyy"),84); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (111, "Tike", to_date("23-Aug-1976","dd-mon-yyyy"),null,100); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (112, "Inn", to_date("15-Nov-1961","dd-mon-yyyy"),to_date("4-Apr-2004","dd-mon-yyyy"),70); 1 row created. SQL> INSERT INTO emp(emp_id, ename, hire_date,end_date, rate)VALUES (113, "Kate", to_date("3-Mar-2004","dd-mon-yyyy"),to_date("31-Oct-2004","dd-mon-yyyy"),300); 1 row created. SQL> SQL> SQL> CREATE TABLE server_usage (
2 pro_id NUMBER(4), 3 emp_id NUMBER, 4 time_log_date DATE, 5 hours_logged NUMBER(8,2), 6 dollars_charged NUMBER(8,2), 7 CONSTRAINT server_usage_pk PRIMARY KEY (pro_id, emp_id, time_log_date) 8 );
Table created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1001,101,to_date("4-Apr-2004","dd-mon-yyyy"),1123,222);
1 row created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1002,102,to_date("4-Apr-2005","dd-mon-yyyy"),1124,223);
1 row created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1003,103,to_date("4-Apr-2006","dd-mon-yyyy"),1125,224);
1 row created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1004,104,to_date("4-Apr-2007","dd-mon-yyyy"),1126,225);
1 row created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1005,105,to_date("4-Apr-2008","dd-mon-yyyy"),1127,226);
1 row created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1001,106,to_date("4-Apr-2009","dd-mon-yyyy"),1128,227);
1 row created. SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
2 VALUES (1002,107,to_date("4-Apr-2010","dd-mon-yyyy"),1129,228);
1 row created. SQL> SQL> SQL> SET ECHO ON SQL> SELECT emp_id
2 FROM emp
3 MINUS
4 SELECT emp_id
5 FROM server_usage;
108
110
111
112
113
5 rows selected. SQL> SQL> SQL> drop table server_usage; Table dropped. SQL> drop table emp; Table dropped. SQL>
</source>
MINUS: returns all those records from the first query, but not the second
<source lang="sql">
SQL> CREATE TABLE EMP (EMPNO NUMBER(4) NOT NULL,
2 ENAME VARCHAR2(10), 3 JOB VARCHAR2(9), 4 MGR NUMBER(4), 5 HIREDATE DATE, 6 SAL NUMBER(7, 2), 7 COMM NUMBER(7, 2), 8 DEPTNO NUMBER(2));
Table created. SQL> SQL> INSERT INTO EMP VALUES (7369, "SMITH", "CLERK", 7902, TO_DATE("17-DEC-1980", "DD-MON-YYYY"), 800, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES (7499, "ALLEN", "SALESMAN", 7698, TO_DATE("20-FEB-1981", "DD-MON-YYYY"), 1600, 300, 30); 1 row created. SQL> INSERT INTO EMP VALUES (7521, "WARD", "SALESMAN", 7698, TO_DATE("22-FEB-1981", "DD-MON-YYYY"), 1250, 500, 30); 1 row created. SQL> INSERT INTO EMP VALUES (7566, "JONES", "MANAGER", 7839, TO_DATE("2-APR-1981", "DD-MON-YYYY"), 2975, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES (7654, "MARTIN", "SALESMAN", 7698,TO_DATE("28-SEP-1981", "DD-MON-YYYY"), 1250, 1400, 30); 1 row created. SQL> INSERT INTO EMP VALUES (7698, "BLAKE", "MANAGER", 7839,TO_DATE("1-MAY-1981", "DD-MON-YYYY"), 2850, NULL, 30); 1 row created. SQL> INSERT INTO EMP VALUES (7782, "CLARK", "MANAGER", 7839,TO_DATE("9-JUN-1981", "DD-MON-YYYY"), 2450, NULL, 10); 1 row created. SQL> INSERT INTO EMP VALUES (7788, "SCOTT", "ANALYST", 7566,TO_DATE("09-DEC-1982", "DD-MON-YYYY"), 3000, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES (7839, "KING", "PRESIDENT", NULL,TO_DATE("17-NOV-1981", "DD-MON-YYYY"), 5000, NULL, 10); 1 row created. SQL> INSERT INTO EMP VALUES (7844, "TURNER", "SALESMAN", 7698,TO_DATE("8-SEP-1981", "DD-MON-YYYY"), 1500, 0, 30); 1 row created. SQL> INSERT INTO EMP VALUES (7876, "ADAMS", "CLERK", 7788,TO_DATE("12-JAN-1983", "DD-MON-YYYY"), 1100, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES (7900, "JAMES", "CLERK", 7698,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 950, NULL, 30); 1 row created. SQL> INSERT INTO EMP VALUES (7902, "FORD", "ANALYST", 7566,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 3000, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES (7934, "MILLER", "CLERK", 7782,TO_DATE("23-JAN-1982", "DD-MON-YYYY"), 1300, NULL, 10); 1 row created. SQL> SQL> -- MINUS set operator returns all those records that are returned from the first query, but not the second. SQL> SQL> select empno, ename
2 from emp
3 where ename like "A%"
4 or ename like "B%"
5 minus
6 select empno, ename
7 from emp
8 where ename like "B%"
9 or ename like "C%";
EMPNO ENAME
----------
7499 ALLEN
7876 ADAMS
SQL> SQL> SQL> SQL> SQL> drop table emp; Table dropped. SQL> SQL> SQL>
</source>
minus with like operator
<source lang="sql">
SQL> SQL> CREATE TABLE employees
2 ( employee_id number(10) not null, 3 last_name varchar2(50) not null, 4 email varchar2(30), 5 hire_date date, 6 job_id varchar2(30), 7 department_id number(10), 8 salary number(6), 9 manager_id number(6) 10 );
Table created. SQL> SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary,department_id ,manager_id)
2 values ( 1001, "Lawson", "lawson@g.ru", "01-JAN-2002","MGR", 30000,1 ,1004);
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id ,manager_id)
2 values ( 1002, "Wells", "wells@g.ru", "01-JAN-2002", "DBA", 20000,2, 1005 );
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id ,manager_id)
2 values( 1003, "Bliss", "bliss@g.ru", "01-JAN-2002", "PROG", 24000,3 ,1004);
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id, manager_id)
2 values( 1004, "Kyte", "tkyte@a.ru", SYSDATE-3650, "MGR",25000 ,4, 1005);
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id, manager_id)
2 values( 1005, "Viper", "sdillon@a .ru", SYSDATE, "PROG", 20000, 1, 1006);
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id,manager_id)
2 values( 1006, "Beck", "clbeck@g.ru", SYSDATE, "PROG", 20000, 2, null);
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id, manager_id)
2 values( 1007, "Java", "java01@g.ru", SYSDATE, "PROG", 20000, 3, 1006);
1 row created. SQL> SQL> insert into employees( employee_id, last_name, email, hire_date, job_id, salary, department_id, manager_id)
2 values( 1008, "Oracle", "wvelasq@g.ru", SYSDATE, "DBA", 20000, 4, 1006);
1 row created. SQL> SQL> select * from employees; EMPLOYEE_ID LAST_NAME EMAIL HIRE_DATE JOB_ID DEPARTMENT_ID SALARY MANAGER_ID
-------------------------------------------------- ------------------------------ --------- ------------------------------ ------------- ---------- ----------
1001 Lawson lawson@g.ru 01-JAN-02 MGR 1 30000 1004
1002 Wells wells@g.ru 01-JAN-02 DBA 2 20000 1005
1003 Bliss bliss@g.ru 01-JAN-02 PROG 3 24000 1004
1004 Kyte tkyte@a.ru 13-JUN-98 MGR 4 25000 1005
1005 Viper sdillon@a .ru 10-JUN-08 PROG 1 20000 1006
1006 Beck clbeck@g.ru 10-JUN-08 PROG 2 20000
1007 Java java01@g.ru 10-JUN-08 PROG 3 20000 1006
EMPLOYEE_ID LAST_NAME EMAIL HIRE_DATE JOB_ID DEPARTMENT_ID SALARY MANAGER_ID
-------------------------------------------------- ------------------------------ --------- ------------------------------ ------------- ---------- ----------
1008 Oracle wvelasq@g.ru 10-JUN-08 DBA 4 20000 1006
8 rows selected. SQL> SQL> select employee_id, last_name
2 from employees 3 where last_name like "A%" 4 or last_name like "B%" 5 minus 6 select employee_id, last_name 7 from employees 8 where last_name like "B%" 9 or last_name like "C%" 10 /
no rows selected SQL> drop table employees; Table dropped. SQL>
</source>
One result set "minus" another result set
<source lang="sql">
SQL> SQL> -- create demo table SQL> create table Employee(
2 ID VARCHAR2(4 BYTE) NOT NULL, 3 First_Name VARCHAR2(10 BYTE), 4 Last_Name VARCHAR2(10 BYTE), 5 Start_Date DATE, 6 End_Date DATE, 7 Salary Number(8,2), 8 City VARCHAR2(10 BYTE), 9 Description VARCHAR2(15 BYTE) 10 ) 11 /
Table created. SQL> SQL> -- prepare data SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values ("01","Jason", "Martin", to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto", "Programmer")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("02","Alison", "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("03","James", "Smith", to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("04","Celia", "Rice", to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("05","Robert", "Black", to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("06","Linda", "Green", to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York", "Tester")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("07","David", "Larry", to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York", "Manager")
3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("08","James", "Cat", to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
3 /
1 row created. SQL> SQL> SQL> SQL> -- display data in the table SQL> select * from Employee
2 /
ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ------------------------------------ ---------- ---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1234.56000000000000 Toronto Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78000000000000 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 6544.78000000000000 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 2344.78000000000000 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 2334.78000000000000 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 4322.78000000000000 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 7897.78000000000000 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1232.78000000000000 Vancouver Tester 8 rows selected. SQL> SQL> SQL> SQL> -- One result set "minus" another result set SQL> select id, last_name
2 from Employee 3 minus 4 select id, last_name 5 from Employee 6 where last_name like "B%" 7 or last_name like "C%";
ID LAST_NAME
----------
01 Martin 02 Mathews 03 Smith 04 Rice 06 Green 07 Larry 6 rows selected. SQL> SQL> SQL> SQL> SQL> -- clean the table SQL> drop table Employee
2 /
Table dropped. SQL> SQL>
</source>
Understanding Intersections and Differences
<source lang="sql">
SQL> SQL> CREATE TABLE empExam (
2 empID INT NOT NULL, 3 ExamID INT NOT NULL, 4 Mark INT, 5 Taken SMALLINT, 6 Comments VARCHAR(255), 7 CONSTRAINT PK_empExam PRIMARY KEY (empID, ExamID));
Table created. SQL> SQL> SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (1,1,55,1,"Satisfactory"); 1 row created. SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (1,2,73,1,"Good result"); 1 row created. SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (2,3,44,1,"Hard"); 1 row created. SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken,Comments) VALUES (2,5,39,0,"Simple"); 1 row created. SQL> INSERT INTO empExam (empID,ExamID,Mark,Taken) VALUES (2,6,63,1); 1 row created. SQL> SQL> SQL> SQL> CREATE TABLE dept (
2 deptID INT NOT NULL PRIMARY KEY, 3 empID INT NOT NULL, 4 ClassID INT NOT NULL, 5 EnrolledOn DATE, 6 Grade INT);
Table created. SQL> SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (1,1,1,DATE "2002-09-23",62); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (2,1,2,DATE "2002-09-30",70); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (3,2,3,DATE "2003-09-23",51); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (4,2,5,DATE "2003-09-23",41); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (5,2,6,DATE "2003-09-23",68); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (6,3,4,DATE "2002-09-30",78); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (7,3,7,DATE "2002-09-30",80); 1 row created. SQL> INSERT INTO dept (deptID,empID,ClassID,EnrolledOn,Grade) VALUES (8,4,8,DATE "2002-09-20",70); 1 row created. SQL> SQL> SQL> SELECT empID
2 FROM empExam
3 WHERE Mark < 40
4 MINUS
5 SELECT empID
6 FROM dept
7 WHERE GRADE > 69
8 ORDER BY empID;
EMPID
2
1 row selected. SQL> SQL> SQL> drop table empExam; Table dropped. SQL> drop table dept; Table dropped.
</source>
Use COUNT to count the rows from a subquery with set operator
<source lang="sql">
SQL> -- SQL> SQL> create table customer(
2 cust_no integer primary key 3 ,lastname varchar2(20) not null 4 ,firstname varchar2(15) not null 5 ,midinit varchar2(1) 6 ,street varchar2(30) 7 ,city varchar2(20) 8 ,state varchar2(2) 9 ,zip varchar2(5) 10 ,zip_4 varchar2(4) 11 ,area_code varchar2(3) 12 ,phone varchar2(8) 13 ,company_name varchar2(50) 14 );
Table created. SQL> SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(1, "Allen", "Joe","J","10 Ave","London","CA","11111","1111","111", "111-1111","Big Company");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(2,"Ward","Sue","W","20 Ave","New York","NY","44444","4444","444", "436-4444","B Company");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(3,"Jason","Pure","J","50 St","Longli","CA","55555","5555","555", "234-4444","C Company");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(4,"Bird","Jill", null,"30 St","Pais","NY","22222","2222","222", "634-7733","D Company");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(5,"Hill","Carl","H","19 Drive","A Town","CA","66666","6566","666", "243-4243","E Company");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(6,"Peter","Yari","P","38 Ave","Small City","NY","77777","7777","777", "454-5443","F Inc");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(7,"Joe","Paula","J","78 St. Apt 3A","Queen City","NY","32322","2323","888", "664-4333","E Inc");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(8,"Chili","Steve","C","38 Ave Apt 62","Mili","CA","88888","8888","787", "456-4566","G Inc");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(9,"Mona","Joe","M","930 Ave933","Kansas City","MO","12345","1234","412", "456-4563","H Inc");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(10,"Hack","Kisi","H","Kings Rd","Bellmore","NY","54321","3898","516", "767-5677","I Inc");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(11,"Bill","Jose","B","12 Giant Rd.","Newton","NJ","23454","1234","958", "123-7367","J Associates");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(12,"Taker","Lawrence","T","1 Sask Rd.","Camp","NJ","19191","3298","928", "123-7384","K Company");
1 row created. SQL> insert into customer(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(13,"Richer","Doris","R","213 Easy Street","WarPease","RI","34343","2112","501", "123-7384","L Inc");
1 row created. SQL> insert into customer( cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone,company_name)
2 values(14,"Pete","Doris","P","9 Ave","New York","NY","45454","4222","112", "123-1234","M Company");
1 row created. SQL> SQL> create table cust_history(
2 cust_no integer primary key 3 ,lastname varchar2(20) not null 4 ,firstname varchar2(15) not null 5 ,midinit varchar2(1) 6 ,street varchar2(30) 7 ,city varchar2(20) 8 ,state varchar2(2) 9 ,zip varchar2(5) 10 ,zip_4 varchar2(4) 11 ,area_code varchar2(3) 12 ,phone varchar2(8) 13 ,company_name varchar2(50) 14 );
Table created. SQL> insert into cust_history(cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone)
2 values(3,"Brad","Ted","T","13 Street","Newton","RI","22222","3333","401", "123-4321");
1 row created. SQL> insert into cust_history( cust_no,lastname,firstname,midinit,street,city,state,zip,zip_4,area_code,phone)
2 values(4,"Wite","Doris","R","94 Ave","New York","NY","22299","3222","212", "123-1234");
1 row created. SQL> SQL> SQL> SQL> select count(*)
2 from (select cust_no, lastname 3 from customer 4 minus 5 select cust_no, lastname 6 from cust_history ); COUNT(*)
14
1 row selected. SQL> SQL> drop table customer; Table dropped. SQL> drop table cust_history; Table dropped. SQL> SQL> --
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