Oracle PL/SQL/Table Joins/Table Join Basics

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Версия от 09:54, 26 мая 2010; Admin (обсуждение | вклад) (1 версия)
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Adding an Analytical Function to a Query that Contains a Join (and Other WHERE Conditions)

   
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    ename              VARCHAR2(10 BYTE),   -- Employee Name
  4    hireDate          DATE,                -- Date Employee Hired
  5    orig_salary        Number(8,2),         -- Orignal Salary
  6    curr_salary        Number(8,2),         -- Current Salary
  7    region             VARCHAR2(1 BYTE)     -- Region where employeed
  8  )
  9  /
Table created.
SQL>
SQL> create table job(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    jobtitle           VARCHAR2(10 BYTE)    -- Employee job title
  4  )
  5  /
Table created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(122,"Alison",to_date("19960321","YYYYMMDD"), 45000,       48000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(123, "James",to_date("19781212","YYYYMMDD"), 23000,       32000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(104,"Celia",to_date("19821024","YYYYMMDD"), 53000,       58000,        "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(105,"Robert",to_date("19840115","YYYYMMDD"), 31000,      36000,        "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(116,"Linda", to_date("19870730","YYYYMMDD"), 43000,       53000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(117,"David", to_date("19901231","YYYYMMDD"), 78000,       85000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(108,"Jode",  to_date("19960917","YYYYMMDD"), 21000,       29000,       "E")
  3  /
1 row created.
SQL>
SQL> -- prepare data for job table
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(101,   "Painter");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(122,   "Tester");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(123,   "Dediator");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(104,   "Chemist");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(105,   "Accountant");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(116,   "Manager");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(117,   "Programmer");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(108,   "Developer");
1 row created.
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
Hit a key to continue
     EMPNO ENAME      HIREDATE  ORIG_SALARY CURR_SALARY R
---------- ---------- --------- ----------- ----------- -
       122 Alison     21-MAR-96       45000       48000 E
       123 James      12-DEC-78       23000       32000 W
       104 Celia      24-OCT-82       53000       58000 E
       105 Robert     15-JAN-84       31000       36000 W
       116 Linda      30-JUL-87       43000       53000 E
       117 David      31-DEC-90       78000       85000 W
       108 Jode       17-SEP-96       21000       29000 E
7 rows selected.
SQL> select * from job;
Hit a key to continue
     EMPNO JOBTITLE
---------- ----------
       101 Painter
       122 Tester
       123 Dediator
       104 Chemist
       105 Accountant
       116 Manager
       117 Programmer
       108 Developer
8 rows selected.
SQL>
SQL>
SQL>
SQL>
SQL> -- Adding an Analytical Function to a Query that Contains a Join (and Other WHERE Conditions)
SQL>
SQL> SELECT e.empno, e.ename, j.jobtitle, e.orig_salary,
  2    RANK() OVER(ORDER BY e.orig_salary desc) rankorder
  3  FROM employee e, job j
  4  WHERE e.orig_salary < 43000
  5    AND e.empno = j.empno
  6  ORDER BY orig_salary desc;
Hit a key to continue
     EMPNO ENAME      JOBTITLE   ORIG_SALARY  RANKORDER
---------- ---------- ---------- ----------- ----------
       105 Robert     Accountant       31000          1
       123 James      Dediator         23000          2
       108 Jode       Developer        21000          3
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> drop table job;
Table dropped.
SQL>
SQL> -- clean the table
SQL> drop table Employee;
Table dropped.
SQL>
SQL>
SQL>



Adding Ordering to the Query Containing the GROUP BY

   

SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    ename              VARCHAR2(10 BYTE),   -- Employee Name
  4    hireDate          DATE,                -- Date Employee Hired
  5    orig_salary        Number(8,2),         -- Orignal Salary
  6    curr_salary        Number(8,2),         -- Current Salary
  7    region             VARCHAR2(1 BYTE)     -- Region where employeed
  8  )
  9  /
Table created.
SQL>
SQL> create table job(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    jobtitle           VARCHAR2(10 BYTE)    -- Employee job title
  4  )
  5  /
Table created.
SQL> -- prepare data for employee table
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(122,"Alison",to_date("19960321","YYYYMMDD"), 45000,       48000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(123, "James",to_date("19781212","YYYYMMDD"), 23000,       32000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(104,"Celia",to_date("19821024","YYYYMMDD"), 53000,       58000,        "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(105,"Robert",to_date("19840115","YYYYMMDD"), 31000,      36000,        "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(116,"Linda", to_date("19870730","YYYYMMDD"), 43000,       53000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(117,"David", to_date("19901231","YYYYMMDD"), 78000,       85000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(108,"Jode",  to_date("19960917","YYYYMMDD"), 21000,       29000,       "E")
  3  /
1 row created.
SQL>
SQL> -- prepare data for job table
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(101,   "Painter");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(122,   "Tester");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(123,   "Dediator");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(104,   "Chemist");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(105,   "Accountant");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(116,   "Manager");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(117,   "Programmer");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(108,   "Developer");
1 row created.
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
Hit a key to continue
     EMPNO ENAME      HIREDATE  ORIG_SALARY CURR_SALARY R
---------- ---------- --------- ----------- ----------- -
       122 Alison     21-MAR-96       45000       48000 E
       123 James      12-DEC-78       23000       32000 W
       104 Celia      24-OCT-82       53000       58000 E
       105 Robert     15-JAN-84       31000       36000 W
       116 Linda      30-JUL-87       43000       53000 E
       117 David      31-DEC-90       78000       85000 W
       108 Jode       17-SEP-96       21000       29000 E
7 rows selected.
SQL> select * from job;
Hit a key to continue
     EMPNO JOBTITLE
---------- ----------
       101 Painter
       122 Tester
       123 Dediator
       104 Chemist
       105 Accountant
       116 Manager
       117 Programmer
       108 Developer
8 rows selected.
SQL> -- Adding Ordering to the Query Containing the GROUP BY
SQL>
SQL>
SQL> SELECT j.jobtitle, COUNT(*), MAX(orig_salary) maxsalary,
  2    MIN(orig_salary) minsalary
  3  FROM employee e, job j
  4  WHERE e.orig_salary < 43000
  5    AND e.empno = j.empno
  6  GROUP BY j.jobtitle
  7  ORDER BY maxsalary;
Hit a key to continue
JOBTITLE     COUNT(*)  MAXSALARY  MINSALARY
---------- ---------- ---------- ----------
Developer           1      21000      21000
Dediator            1      23000      23000
Accountant          1      31000      31000
SQL>
SQL>
SQL> drop table job;
Table dropped.
SQL>
SQL> -- clean the table
SQL> drop table Employee;
Table dropped.
SQL>
SQL>



Add the USING clause

    
SQL>
SQL> create table department(
  2          dept_no                 integer      primary key
  3         ,dept_name               varchar(20)      not null
  4         ,mgr_no                  integer
  5  );
Table created.
SQL>
SQL> insert into department(dept_no, dept_name, mgr_no)values(1, "Design", 1);
1 row created.
SQL> insert into department(dept_no, dept_name, mgr_no)values(2, "Sales", 1);
1 row created.
SQL> insert into department(dept_no, dept_name, mgr_no)values(3, "Development", 1);
1 row created.
SQL>
SQL> create table employee(
  2           emp_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          ,salary                 number(3)
 14          ,birthdate              date
 15          ,hiredate               date
 16          ,title                  varchar2(20)
 17          ,dept_no                integer
 18          ,mgr                    integer
 19          ,region                 number
 20          ,division               number
 21          ,total_sales            number
 22  );
Table created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (1,"Anderson","Nancy","N","33 Ave","London","NY","11111","1111","212","234-1111",3.75,"21-mar-1927","1-feb-1947","Sales Manager",2,null,100,10,40000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (2,"Last","First","F","12 Ave","Paris","CA","22222","2222","221","867-2222",7.75,"14-feb-1976","15-mar-1985","Sales Clerk",2,1,100,10,10000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (3,"Wash","Georgia","G","1 Street14","Barton","NJ","33333","3333","214","340-3333",11.50,"2-jul-1977","21-apr-2004","Designer",1,2,100,10,40000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (4,"Bush","Dave","D","56 Street","Island","RI","44444","4444","215","777-4444",21.65,"15-may-1945","2-aug-1975","Designer",1,2,100,10,40000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (5,"Will","Robin","W","56 Street","Island","MA","55555","5555","216","777-5555",24.65,"10-dec-1980","2-aug-2007","Designer",1,5,100,10,40000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (6,"Pete","Mona","M","13 Ave","York","MO","66666","6666","217","111-6666",9,"14-feb-1966","15-mar-1985","Sales Clerk",2,5,100,10,40000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (7,"Roke","John","J","67 Ave","New York","BC","77777","7777","218","122-7777",10.00,"14-jun-1955","15-mar-1975","Accountant",3,2,100,10,40000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2               values (8,"Horry","Tedi","T","1236 Lane","Newton","NY","88888","8888","219","222-8888",13.00,"10-jun-1955","15-aug-1985","Sales Representative",3,2,100,10,50000);
1 row created.
SQL> insert into employee(emp_no, lastname, firstname, midinit, street, city, state, zip,zip_4, area_code, phone, salary, birthdate, hiredate,title, dept_no, mgr, region, division, total_sales)
  2                values (9,"Bar","Candi","C","400 East Street","Yorken","NY","99999","9999","220","321-9999",12.00,"10-oct-1933","15-jan-1969","Sales Representative",3,5,100,10,35000);
1 row created.
SQL>
SQL>
SQL> select dept_name, lastname
  2  from department inner join employee
  3       using (dept_no)
  4  /
DEPT_NAME            LASTNAME
-------------------- --------------------
Sales                Anderson
Sales                Last
Design               Wash
Design               Bush
Design               Will
Sales                Pete
Development          Roke
Development          Horry
Development          Bar
9 rows selected.
SQL>
SQL>
SQL> drop table department;
Table dropped.
SQL> drop table employee;
Table dropped.
SQL> --



Get Categories and Products (with Alternate Join Syntax)

   
SQL>
SQL>
SQL>
SQL> CREATE TABLE Product (
  2  ProductID INT NOT NULL PRIMARY KEY,
  3  Name VARCHAR(50) NOT NULL,
  4  Description VARCHAR(1000) NOT NULL,
  5  Price NUMBER NULL,
  6  ImagePath VARCHAR(50) NULL,
  7  soldout NUMBER(1,0) NULL,
  8  Promotion NUMBER(1,0) NULL);
Table created.
SQL>
SQL> CREATE SEQUENCE ProductIDSeq;
Sequence created.
SQL>
SQL> CREATE OR REPLACE TRIGGER ProductAutonumberTrigger
  2  BEFORE INSERT ON Product
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT ProductIDSeq.NEXTVAL
  6     INTO :NEW.ProductID FROM DUAL;
  7  END;
  8  /
Trigger created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Pen", "Ball Pen",5.99, "pen.jpg", 1, 0);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Ruler", "Long",14.99, "ruler.jpg", 0, 0);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Desk", "Computer Desk",5.99, "desk.jpg", 0, 1);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("PC", "Notebook",49.99, "pc.jpg", 0, 1);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Mouse", "Wireless",9.99, "mouse.jpg",  1, 0);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Keyboard", "keyboard",3.75, "keyboard.jpg", 0, 0);
1 row created.
SQL>
SQL> CREATE TABLE ProductCategory (
  2  ProductID INT NOT NULL,
  3  CategoryID INT NOT NULL,
  4  PRIMARY KEY (ProductID, CategoryID)
  5  );
Table created.
SQL>
SQL>
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (1,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,1);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (3,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (4,1);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (5,2);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,4);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (7,4);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (8,5);
1 row created.
SQL>
SQL>
SQL> CREATE TABLE Category (
  2  CategoryID INT NOT NULL PRIMARY KEY,
  3  DepartmentID INT,
  4  Name VARCHAR(50),
  5  Description VARCHAR (200) NULL);
Table created.
SQL>
SQL> CREATE SEQUENCE CategoryIDSeq;
Sequence created.
SQL>
SQL> CREATE OR REPLACE TRIGGER CategoryAutonumberTrigger
  2  BEFORE INSERT ON Category
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT CategoryIDSeq.NEXTVAL
  6     INTO :NEW.CategoryID FROM DUAL;
  7  END;
  8  /
Trigger created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (1, "Local", "In town");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (1, "Remote", "Telecommute");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (2, "Masks", "By bits");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (3, "Wireless", "Not connected");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (3, "Wired", "Connected");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT C.Name as "Category Name", P.Name as "Product Name"
  2  FROM Product P, ProductCategory PC, Category C
  3  WHERE P.ProductID = PC.ProductID AND PC.CategoryID = C.CategoryID
  4  ORDER BY C.Name, P.Name;
Category Name
--------------------------------------------------
Product Name
--------------------------------------------------
Local
PC
Local
Ruler
Masks
Desk
Masks
Keyboard
Masks
Pen
Masks
Ruler
Remote
Mouse
Wireless
Keyboard

8 rows selected.
SQL>
SQL>
SQL> drop table Product;
Table dropped.
SQL> drop table ProductCategory;
Table dropped.
SQL> drop table Category;
Table dropped.
SQL> drop sequence CategoryIDSeq;
Sequence dropped.
SQL> drop sequence ProductIDSeq;
Sequence dropped.
SQL>



Get Categories and Products (with Joins)

   
SQL>
SQL> CREATE TABLE Product (
  2  ProductID INT NOT NULL PRIMARY KEY,
  3  Name VARCHAR(50) NOT NULL,
  4  Description VARCHAR(1000) NOT NULL,
  5  Price NUMBER NULL,
  6  ImagePath VARCHAR(50) NULL,
  7  soldout NUMBER(1,0) NULL,
  8  Promotion NUMBER(1,0) NULL);
Table created.
SQL>
SQL> CREATE SEQUENCE ProductIDSeq;
Sequence created.
SQL>
SQL> CREATE OR REPLACE TRIGGER ProductAutonumberTrigger
  2  BEFORE INSERT ON Product
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT ProductIDSeq.NEXTVAL
  6     INTO :NEW.ProductID FROM DUAL;
  7  END;
  8  /
Trigger created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Pen", "Ball Pen",5.99, "pen.jpg", 1, 0);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Ruler", "Long",14.99, "ruler.jpg", 0, 0);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Desk", "Computer Desk",5.99, "desk.jpg", 0, 1);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("PC", "Notebook",49.99, "pc.jpg", 0, 1);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Mouse", "Wireless",9.99, "mouse.jpg",  1, 0);
1 row created.
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Keyboard", "keyboard",3.75, "keyboard.jpg", 0, 0);
1 row created.
SQL>
SQL>
SQL> CREATE TABLE ProductCategory (
  2  ProductID INT NOT NULL,
  3  CategoryID INT NOT NULL,
  4  PRIMARY KEY (ProductID, CategoryID)
  5  );
Table created.
SQL>
SQL>
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (1,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,1);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (3,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (4,1);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (5,2);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,3);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,4);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (7,4);
1 row created.
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (8,5);
1 row created.
SQL>
SQL>
SQL> CREATE TABLE Category (
  2  CategoryID INT NOT NULL PRIMARY KEY,
  3  DepartmentID INT NOT NULL,
  4  Name VARCHAR(50) NOT NULL,
  5  Description VARCHAR (200) NULL);
Table created.
SQL>
SQL> CREATE SEQUENCE CategoryIDSeq;
Sequence created.
SQL>
SQL> CREATE OR REPLACE TRIGGER CategoryAutonumberTrigger
  2  BEFORE INSERT ON Category
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT CategoryIDSeq.NEXTVAL
  6     INTO :NEW.CategoryID FROM DUAL;
  7  END;
  8  /
Trigger created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (1, "Local", "In town");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (1, "Remote", "Telecommute");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (2, "Masks", "By bits");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (3, "Wireless", "Not connected");
1 row created.
SQL> INSERT INTO Category (DepartmentID, Name, Description) VALUES (3, "Wired", "Connected");
1 row created.
SQL>
SQL>
SQL> SELECT C.Name as "Category Name", P.Name as "Product Name"
  2  FROM Product P
  3  INNER JOIN ProductCategory PC ON P.ProductID = PC.ProductID
  4  INNER JOIN Category C ON PC.CategoryID = C.CategoryID
  5  ORDER BY C.Name, P.Name;
Category Name
--------------------------------------------------
Product Name
--------------------------------------------------
Local
PC
Local
Ruler
Masks
Desk
Masks
Keyboard
Masks
Pen
Masks
Ruler
Remote
Mouse
Wireless
Keyboard

8 rows selected.
SQL>
SQL>
SQL>
SQL> drop table Product;
Table dropped.
SQL> drop table ProductCategory;
Table dropped.
SQL> drop table Category;
Table dropped.
SQL> drop sequence CategoryIDSeq;
Sequence dropped.
SQL> drop sequence ProductIDSeq;
Sequence dropped.



How Many Featured Products By Department with JOINs

    
SQL>
SQL>
SQL> CREATE TABLE Department (
  2  DepartmentID INT NOT NULL PRIMARY KEY,
  3  Name VARCHAR(50) NOT NULL,
  4  Description VARCHAR(200) NULL);
SQL>
SQL> CREATE SEQUENCE DepartmentIDSeq;
SQL>
SQL> CREATE OR REPLACE TRIGGER DepartmentAutonumberTrigger
  2  BEFORE INSERT ON Department
  3  FOR EACH ROW
  4  BEGIN
  5    SELECT DepartmentIDSeq.NEXTVAL
  6    INTO :NEW.DepartmentID FROM DUAL;
  7  END;
  8  /
SQL>
SQL> INSERT INTO Department (Name, Description)
  2     VALUES ("Software", "Coding");
SQL> INSERT INTO Department (Name, Description)
  2     VALUES ("Hardware", "Building");
SQL> INSERT INTO Department (Name, Description)
  2     VALUES ("QA", "Testing");
SQL>
SQL>
SQL>
SQL>
SQL> CREATE TABLE Category (
  2  CategoryID INT NOT NULL PRIMARY KEY,
  3  DepartmentID INT NOT NULL,
  4  Name VARCHAR(50) NOT NULL,
  5  Description VARCHAR (200) NULL);
SQL>
SQL> CREATE SEQUENCE CategoryIDSeq;
SQL>
SQL> CREATE OR REPLACE TRIGGER CategoryAutonumberTrigger
  2  BEFORE INSERT ON Category
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT CategoryIDSeq.NEXTVAL
  6     INTO :NEW.CategoryID FROM DUAL;
  7  END;
  8  /
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (1, "Local", "In town");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (1, "Remote", "Telecommute");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (2, "Masks", "By bits");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (3, "Wireless", "Not connected");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (3, "Wired", "Connected");
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> CREATE TABLE Product (
  2  ProductID INT NOT NULL PRIMARY KEY,
  3  Name VARCHAR(50) NOT NULL,
  4  Description VARCHAR(1000) NOT NULL,
  5  Price NUMBER NULL,
  6  ImagePath VARCHAR(50) NULL,
  7  soldout NUMBER(1,0) NULL,
  8  Promotion NUMBER(1,0) NULL);
SQL>
SQL> CREATE SEQUENCE ProductIDSeq;
SQL>
SQL> CREATE OR REPLACE TRIGGER ProductAutonumberTrigger
  2  BEFORE INSERT ON Product
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT ProductIDSeq.NEXTVAL
  6     INTO :NEW.ProductID FROM DUAL;
  7  END;
  8  /
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Pen", "Ball Pen",5.99, "pen.jpg", 1, 0);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Ruler","Long",14.99, "ruler.jpg", 0, 0);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Desk", "Computer Desk",5.99, "desk.jpg", 0, 1);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("PC", "Notebook",49.99, "pc.jpg", 0, 1);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Mouse", "Wireless",9.99, "mouse.jpg",  1, 0);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Keyboard","keyboard",3.75, "keyboard.jpg", 0, 0);
SQL>
SQL>
SQL> CREATE TABLE ProductCategory (
  2  ProductID INT NOT NULL,
  3  CategoryID INT NOT NULL,
  4  PRIMARY KEY (ProductID, CategoryID)
  5  );
SQL>
SQL>
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (1,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,1);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (3,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (4,1);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (5,2);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,4);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (7,4);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (8,5);
SQL>
SQL>
SQL> SELECT Department.Name AS "Department",
  2         COUNT(Product.Name) AS "Featured Products"
  3  FROM Product
  4     INNER JOIN ProductCategory
  5     ON Product.ProductID = ProductCategory.ProductID
  6     INNER JOIN Category
  7     ON ProductCategory.CategoryID = Category.CategoryID
  8     INNER JOIN Department
  9     ON Category.DepartmentID = Department.DepartmentID
 10  WHERE Product.Promotion = 1
 11  GROUP BY Department.Name
 12  ORDER BY Department.Name;
Hardware
                1
Software
                1
SQL>
SQL>
SQL>
SQL> drop table department;
SQL> drop sequence DepartmentIDSeq;
SQL> drop table Product;
SQL> drop table ProductCategory;
SQL> drop table Category;
SQL> drop sequence CategoryIDSeq;
SQL> drop sequence ProductIDSeq;



How Many Products By Department with JOINs

    
SQL>
SQL>
SQL> CREATE TABLE Department (
  2  DepartmentID INT NOT NULL PRIMARY KEY,
  3  Name VARCHAR(50) NOT NULL,
  4  Description VARCHAR(200) NULL);
SQL>
SQL> CREATE SEQUENCE DepartmentIDSeq;
SQL>
SQL> CREATE OR REPLACE TRIGGER DepartmentAutonumberTrigger
  2  BEFORE INSERT ON Department
  3  FOR EACH ROW
  4  BEGIN
  5    SELECT DepartmentIDSeq.NEXTVAL
  6    INTO :NEW.DepartmentID FROM DUAL;
  7  END;
  8  /
SQL>
SQL> INSERT INTO Department (Name, Description)
  2     VALUES ("Software", "Coding");
SQL> INSERT INTO Department (Name, Description)
  2     VALUES ("Hardware", "Building");
SQL> INSERT INTO Department (Name, Description)
  2     VALUES ("QA", "Testing");
SQL>
SQL>
SQL>
SQL>
SQL> CREATE TABLE Category (
  2  CategoryID INT NOT NULL PRIMARY KEY,
  3  DepartmentID INT NOT NULL,
  4  Name VARCHAR(50) NOT NULL,
  5  Description VARCHAR (200) NULL);
SQL>
SQL> CREATE SEQUENCE CategoryIDSeq;
SQL>
SQL> CREATE OR REPLACE TRIGGER CategoryAutonumberTrigger
  2  BEFORE INSERT ON Category
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT CategoryIDSeq.NEXTVAL
  6     INTO :NEW.CategoryID FROM DUAL;
  7  END;
  8  /
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (1, "Local", "In town");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (1, "Remote", "Telecommute");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (2, "Masks", "By bits");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (3, "Wireless", "Not connected");
SQL> INSERT INTO Category (DepartmentID, Name, Description)
  2     VALUES (3, "Wired", "Connected");
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> CREATE TABLE Product (
  2  ProductID INT NOT NULL PRIMARY KEY,
  3  Name VARCHAR(50) NOT NULL,
  4  Description VARCHAR(1000) NOT NULL,
  5  Price NUMBER NULL,
  6  ImagePath VARCHAR(50) NULL,
  7  soldout NUMBER(1,0) NULL,
  8  Promotion NUMBER(1,0) NULL);
SQL>
SQL> CREATE SEQUENCE ProductIDSeq;
SQL>
SQL> CREATE OR REPLACE TRIGGER ProductAutonumberTrigger
  2  BEFORE INSERT ON Product
  3  FOR EACH ROW
  4  BEGIN
  5     SELECT ProductIDSeq.NEXTVAL
  6     INTO :NEW.ProductID FROM DUAL;
  7  END;
  8  /
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Pen", "Ball Pen",5.99, "pen.jpg", 1, 0);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Ruler","Long",14.99, "ruler.jpg", 0, 0);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("Desk", "Computer Desk",5.99, "desk.jpg", 0, 1);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath, soldout, Promotion)
  2  VALUES ("PC", "Notebook",49.99, "pc.jpg", 0, 1);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Mouse", "Wireless",9.99, "mouse.jpg",  1, 0);
SQL>
SQL> INSERT INTO Product (Name, Description, Price, ImagePath,soldout, Promotion)
  2  VALUES ("Keyboard","keyboard",3.75, "keyboard.jpg", 0, 0);
SQL>
SQL>
SQL> CREATE TABLE ProductCategory (
  2  ProductID INT NOT NULL,
  3  CategoryID INT NOT NULL,
  4  PRIMARY KEY (ProductID, CategoryID)
  5  );
SQL>
SQL>
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (1,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,1);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (2,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (3,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (4,1);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (5,2);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,3);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (6,4);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (7,4);
SQL> INSERT INTO ProductCategory (ProductID, CategoryID) VALUES (8,5);
SQL>
SQL> SELECT Department.Name AS "Department",
  2         COUNT(Product.Name) AS "Products"
  3  FROM Product
  4     INNER JOIN ProductCategory
  5     ON Product.ProductID = ProductCategory.ProductID
  6     INNER JOIN Category
  7     ON ProductCategory.CategoryID = Category.CategoryID
  8     INNER JOIN Department
  9     ON Category.DepartmentID = Department.DepartmentID
 10  GROUP BY Department.Name
 11  ORDER BY Department.Name;
Hardware
         4
QA
         1
Software
         3
SQL>
SQL>
SQL> drop table department;
SQL> drop sequence DepartmentIDSeq;
SQL> drop table Product;
SQL> drop table ProductCategory;
SQL> drop table Category;
SQL> drop sequence CategoryIDSeq;
SQL> drop sequence ProductIDSeq;



Joining table to use between ... and clause

   
SQL> create table emp
  2  ( empno      NUMBER(4)    constraint E_PK primary key
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , sal        NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2)    default 10
 11  ) ;
Table created.
SQL> insert into emp values(1,"Tom","N",   "Coder", 13,date "1965-12-17",  800 , NULL,  20);
1 row created.
SQL> insert into emp values(2,"Jack","JAM", "Tester",6,date "1961-02-20",  1600, 300,   30);
1 row created.
SQL> insert into emp values(3,"Wil","TF" ,  "Tester",6,date "1962-02-22",  1250, 500,   30);
1 row created.
SQL> insert into emp values(4,"Jane","JM",  "Designer", 9,date "1967-04-02",  2975, NULL,  20);
1 row created.
SQL> insert into emp values(5,"Mary","P",  "Tester",6,date "1956-09-28",  1250, 1400,  30);
1 row created.
SQL> insert into emp values(6,"Black","R",   "Designer", 9,date "1963-11-01",  2850, NULL,  30);
1 row created.
SQL> insert into emp values(7,"Chris","AB",  "Designer", 9,date "1965-06-09",  2450, NULL,  10);
1 row created.
SQL> insert into emp values(8,"Smart","SCJ", "Coder", 4,date "1959-11-26",  3000, NULL,  20);
1 row created.
SQL> insert into emp values(9,"Peter","CC",   "Designer",NULL,date "1952-11-17",  5000, NULL,  10);
1 row created.
SQL> insert into emp values(10,"Take","JJ", "Tester",6,date "1968-09-28",  1500, 0,     30);
1 row created.
SQL> insert into emp values(11,"Ana","AA",  "Coder", 8,date "1966-12-30",  1100, NULL,  20);
1 row created.
SQL> insert into emp values(12,"Jane","R",   "Manager",   6,date "1969-12-03",  800 , NULL,  30);
1 row created.
SQL> insert into emp values(13,"Fake","MG",   "Coder", 4,date "1959-02-13",  3000, NULL,  20);
1 row created.
SQL> insert into emp values(14,"Mike","TJA","Manager",   7,date "1962-01-23",  1300, NULL,  10);
1 row created.
SQL>
SQL>
SQL> create table salary
  2  ( grade      NUMBER(2)   constraint S_PK
  3                           primary key
  4  , lowerlimit NUMBER(6,2)
  5  , upperlimit NUMBER(6,2)
  6  , bonus      NUMBER(6,2)
  7  , constraint S_LO_UP_CHK check
  8                           (lowerlimit <= upperlimit)
  9  ) ;
Table created.
SQL>
SQL> insert into salary values (1,  700,1200,   0);
1 row created.
SQL> insert into salary values (2, 1201,1400,  50);
1 row created.
SQL> insert into salary values (3, 1401,2000, 100);
1 row created.
SQL> insert into salary values (4, 2001,3000, 200);
1 row created.
SQL> insert into salary values (5, 3001,9999, 500);
1 row created.
SQL>
SQL> select e.ename           emp
  2  ,      12*e.sal+s.bonus total_salary
  3  from   emp e
  4  ,      salary s
  5  where  e.sal between s.lowerlimit
  6                    and s.upperlimit;
EMP      TOTAL_SALARY
-------- ------------
Tom              9600
Ana             13200
Jane             9600
Wil             15050
Mary            15050
Mike            15650
Jack            19300
Take            18100
Jane            35900
Black           34400
Chris           29600
Smart           36200
Fake            36200
Peter           60500
14 rows selected.
SQL> drop table emp;
Table dropped.
SQL> drop table salary;
Table dropped.



Join table using

   
SQL> create table emp
  2  ( empno      NUMBER(4)    constraint E_PK primary key
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , sal       NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2)    default 10
 11  ) ;
Table created.
SQL> insert into emp values(1,"Tom","N",   "Coder", 13,date "1965-12-17",  800 , NULL,  20);
1 row created.
SQL> insert into emp values(2,"Jack","JAM", "Tester",6,date "1961-02-20",  1600, 300,   30);
1 row created.
SQL> insert into emp values(3,"Wil","TF" ,  "Tester",6,date "1962-02-22",  1250, 500,   30);
1 row created.
SQL> insert into emp values(4,"Jane","JM",  "Designer", 9,date "1967-04-02",  2975, NULL,  20);
1 row created.
SQL> insert into emp values(5,"Mary","P",  "Tester",6,date "1956-09-28",  1250, 1400,  30);
1 row created.
SQL> insert into emp values(6,"Black","R",   "Designer", 9,date "1963-11-01",  2850, NULL,  30);
1 row created.
SQL> insert into emp values(7,"Chris","AB",  "Designer", 9,date "1965-06-09",  2450, NULL,  10);
1 row created.
SQL> insert into emp values(8,"Smart","SCJ", "Coder", 4,date "1959-11-26",  3000, NULL,  20);
1 row created.
SQL> insert into emp values(9,"Peter","CC",   "Designer",NULL,date "1952-11-17",  5000, NULL,  10);
1 row created.
SQL> insert into emp values(10,"Take","JJ", "Tester",6,date "1968-09-28",  1500, 0,     30);
1 row created.
SQL> insert into emp values(11,"Ana","AA",  "Coder", 8,date "1966-12-30",  1100, NULL,  20);
1 row created.
SQL> insert into emp values(12,"Jane","R",   "Manager",   6,date "1969-12-03",  800 , NULL,  30);
1 row created.
SQL> insert into emp values(13,"Fake","MG",   "Coder", 4,date "1959-02-13",  3000, NULL,  20);
1 row created.
SQL> insert into emp values(14,"Mike","TJA","Manager",   7,date "1962-01-23",  1300, NULL,  10);
1 row created.
SQL> create table history
  2  ( empno      NUMBER(4)
  3  , beginyear  NUMBER(4)
  4  , begindate  DATE
  5  , enddate    DATE
  6  , deptno     NUMBER(2)
  7  , sal       NUMBER(6,2)
  8  , comments   VARCHAR2(60)
  9  , constraint H_PK         primary key(empno,begindate)
 10  , constraint H_BEG_END    check      (begindate < enddate)
 11  ) ;
Table created.
SQL>
SQL>
SQL> alter session  set NLS_DATE_FORMAT="DD-MM-YYYY";
Session altered.
SQL>
SQL> insert into history values (1,2000,"01-01-2000","01-02-2000",40, 950,"");
1 row created.
SQL> insert into history values (1,2000,"01-02-2000", NULL       ,20, 800,"restarted");
1 row created.
SQL> insert into history values (2,2009,"01-11-2009", NULL       ,30,1600,"just hired");
1 row created.
SQL> insert into history values (3,1987,"01-08-1987","01-01-1989",30,1000,"On training");
1 row created.
SQL> insert into history values (3,2000,"01-02-2000", NULL       ,30,1250,"");
1 row created.
SQL>
SQL> select e.ename, e.bdate
  2  ,      h.deptno, h.sal
  3  from   emp e
  4         join
  5         history h
  6         using (empno)
  7  where  e.job = "Manager";
no rows selected
SQL>
SQL> drop table history;
Table dropped.
SQL> drop table emp;
Table dropped.



Join with a subquery

   
SQL>
SQL> create table emp
  2  ( empno      NUMBER(4)    constraint E_PK primary key
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , sal       NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2)    default 10
 11  ) ;
Table created.
SQL> insert into emp values(1,"Tom","N",   "TRAINER", 13,date "1965-12-17",  800 , NULL,  20);
1 row created.
SQL> insert into emp values(2,"Jack","JAM", "Tester",6,date "1961-02-20",  1600, 300,   30);
1 row created.
SQL> insert into emp values(3,"Wil","TF" ,  "Tester",6,date "1962-02-22",  1250, 500,   30);
1 row created.
SQL> insert into emp values(4,"Jane","JM",  "Designer", 9,date "1967-04-02",  2975, NULL,  20);
1 row created.
SQL> insert into emp values(5,"Mary","P",  "Tester",6,date "1956-09-28",  1250, 1400,  30);
1 row created.
SQL> insert into emp values(6,"Black","R",   "Designer", 9,date "1963-11-01",  2850, NULL,  30);
1 row created.
SQL> insert into emp values(7,"Chris","AB",  "Designer", 9,date "1965-06-09",  2450, NULL,  10);
1 row created.
SQL> insert into emp values(8,"Smart","SCJ", "TRAINER", 4,date "1959-11-26",  3000, NULL,  20);
1 row created.
SQL> insert into emp values(9,"Peter","CC",   "Designer",NULL,date "1952-11-17",  5000, NULL,  10);
1 row created.
SQL> insert into emp values(10,"Take","JJ", "Tester",6,date "1968-09-28",  1500, 0,     30);
1 row created.
SQL> insert into emp values(11,"Ana","AA",  "TRAINER", 8,date "1966-12-30",  1100, NULL,  20);
1 row created.
SQL> insert into emp values(12,"Jane","R",   "Manager",   6,date "1969-12-03",  800 , NULL,  30);
1 row created.
SQL> insert into emp values(13,"Fake","MG",   "TRAINER", 4,date "1959-02-13",  3000, NULL,  20);
1 row created.
SQL> insert into emp values(14,"Mike","TJA","Manager",   7,date "1962-01-23",  1300, NULL,  10);
1 row created.
SQL>
SQL> select e.ename, e.init, e.sal
  2  from   emp e
  3         join
  4        (select   x.deptno
  5         ,        avg(x.sal) avg_sal
  6         from     emp x
  7         group by x.deptno) g
  8         using (deptno)
  9  where  e.sal > g.avg_sal;
ENAME    INIT         SAL
-------- ----- ----------
Peter    CC          5000
Jane     JM          2975
Fake     MG          3000
Smart    SCJ         3000
Jack     JAM         1600
Black    R           2850
6 rows selected.
SQL>
SQL> drop table emp;
Table dropped.
SQL>



Nested Multi-Table Equi-Joins

   
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> CREATE TABLE Exam (
  2     ExamID      INT NOT NULL PRIMARY KEY,
  3     CourseID    INT NOT NULL,
  4     InstructorID INT NOT NULL,
  5     SustainedOn DATE,
  6     Comments    VARCHAR(255));
SQL>
SQL> CREATE TABLE emp (
  2     empID INT NOT NULL PRIMARY KEY,
  3     Name      VARCHAR(50) NOT NULL);
Table created.
SQL> INSERT INTO emp (empID,Name) VALUES (1,"Tom");
1 row created.
SQL> INSERT INTO emp (empID,Name) VALUES (2,"Jack");
1 row created.
SQL> INSERT INTO emp (empID,Name) VALUES (3,"Mary");
1 row created.
SQL> INSERT INTO emp (empID,Name) VALUES (4,"Bill");
1 row created.
SQL> INSERT INTO emp (empID,Name) VALUES (5,"Cat");
1 row created.
SQL> INSERT INTO emp (empID,Name) VALUES (6,"Victor");
1 row created.
SQL>
SQL> SELECT empExam.ExamID,
  2         empExam.Mark,
  3         Exam.SustainedOn,
  4         emp.Name
  5  FROM Exam
  6     INNER JOIN (emp
  7        INNER JOIN empExam ON emp.empID = empExam.empID)
  8     ON Exam.ExamID = empExam.ExamID
  9  ORDER BY empExam.ExamID;
    EXAMID       MARK SUSTAINED
---------- ---------- ---------
NAME
--------------------------------------------------
         1         55 12-MAR-03
Tom
         2         73 13-MAR-03
Tom
         3         44 11-MAR-03
Jack
         5         39 19-MAR-03
Jack

4 rows selected.
SQL>
SQL>
SQL> drop table emp;
Table dropped.
SQL> drop table empExam;
Table dropped.
SQL> drop table exam;
Table dropped.



Non-Equi Joins

    
SQL>
SQL> CREATE TABLE Room (
  2     RoomID   INT NOT NULL PRIMARY KEY,
  3     Comments VARCHAR(50),
  4     Capacity INT);
Table created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (1,"Main hall",500);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (2,"Science Department",200);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (3,"Science Room 1",100);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (4,"Languages Block",300);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (5,"Languages Room 1",75);
1 row created.
SQL>
SQL>
SQL>
SQL> CREATE TABLE Class (
  2     ClassID     INT NOT NULL PRIMARY KEY,
  3     CourseID    INT NOT NULL,
  4     InstructorID INT NOT NULL,
  5     RoomID      INT NOT NULL,
  6     Time        VARCHAR(50));
Table created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (1,1,1,6,"Mon 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (2,2,1,5,"Mon 11:00-12:00, Thu 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (3,3,2,3,"Mon 14:00-16:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (4,4,3,2,"Tue 10:00-12:00, Thu 14:00-15:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (5,5,2,9,"Tue 14:00-16:00");
1 row created.
SQL>
SQL>
SQL> SELECT Room.RoomID, Class.Time
  2  FROM Room JOIN Class ON Room.RoomID <> Class.RoomID;
    ROOMID TIME
---------- --------------------------------------------------
         1 Mon 09:00-11:00
         2 Mon 09:00-11:00
         3 Mon 09:00-11:00
         4 Mon 09:00-11:00
         5 Mon 09:00-11:00
         1 Mon 11:00-12:00, Thu 09:00-11:00
         2 Mon 11:00-12:00, Thu 09:00-11:00
         3 Mon 11:00-12:00, Thu 09:00-11:00
         4 Mon 11:00-12:00, Thu 09:00-11:00
         1 Mon 14:00-16:00
         2 Mon 14:00-16:00
         4 Mon 14:00-16:00
         5 Mon 14:00-16:00
         1 Tue 10:00-12:00, Thu 14:00-15:00
         3 Tue 10:00-12:00, Thu 14:00-15:00
         4 Tue 10:00-12:00, Thu 14:00-15:00
         5 Tue 10:00-12:00, Thu 14:00-15:00
         1 Tue 14:00-16:00
         2 Tue 14:00-16:00
         3 Tue 14:00-16:00
         4 Tue 14:00-16:00
         5 Tue 14:00-16:00
22 rows selected.
SQL>
SQL>
SQL> drop table room;
Table dropped.
SQL> drop table class;
Table dropped.



Supplying Table Aliases

   

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> CREATE TABLE DEPT (DEPTNO NUMBER(2),DNAME VARCHAR2(14),LOC VARCHAR2(13) );
Table created.
SQL>
SQL> INSERT INTO DEPT VALUES (10, "ACCOUNTING", "NEW YORK");
1 row created.
SQL> INSERT INTO DEPT VALUES (20, "RESEARCH", "DALLAS");
1 row created.
SQL> INSERT INTO DEPT VALUES (30, "SALES", "CHICAGO");
1 row created.
SQL> INSERT INTO DEPT VALUES (40, "OPERATIONS", "BOSTON");
1 row created.
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
      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
14 rows selected.
SQL>
SQL> select * from dept;
    DEPTNO DNAME          LOC
---------- -------------- -------------
        10 ACCOUNTING     NEW YORK
        20 RESEARCH       DALLAS
        30 SALES          CHICAGO
        40 OPERATIONS     BOSTON
SQL>
SQL>
SQL> -- Supplying Table Aliases
SQL>
SQL> SELECT emp.ename, dept.dname
  2  FROM emp, dept
  3  WHERE emp.deptno = dept.deptno;
ENAME      DNAME
---------- --------------
SMITH      RESEARCH
ALLEN      SALES
WARD       SALES
JONES      RESEARCH
MARTIN     SALES
BLAKE      SALES
CLARK      ACCOUNTING
SCOTT      RESEARCH
KING       ACCOUNTING
TURNER     SALES
ADAMS      RESEARCH
JAMES      SALES
FORD       RESEARCH
MILLER     ACCOUNTING
14 rows selected.
SQL>
SQL>
SQL>
SQL> drop table dept;
Table dropped.
SQL> drop table emp;
Table dropped.
SQL>
SQL>
SQL>



The query shows that the join is performed with the other WHERE conditions

   

SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    ename              VARCHAR2(10 BYTE),   -- Employee Name
  4    hireDate          DATE,                -- Date Employee Hired
  5    orig_salary        Number(8,2),         -- Orignal Salary
  6    curr_salary        Number(8,2),         -- Current Salary
  7    region             VARCHAR2(1 BYTE)     -- Region where employeed
  8  )
  9  /
Table created.
SQL>
SQL> create table job(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    jobtitle           VARCHAR2(10 BYTE)    -- Employee job title
  4  )
  5  /
Table created.
SQL> -- prepare data for employee table
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2               values (101,"Jason",to_date("19960725","YYYYMMDD"), 34000,        44000        "W")
  3  /
             values (101,"Jason",to_date("19960725","YYYYMMDD"), 34000,        44000        "W")
                                                                                            *
ERROR at line 2:
ORA-00917: missing comma

SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(122,"Alison",to_date("19960321","YYYYMMDD"), 45000,       48000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(123, "James",to_date("19781212","YYYYMMDD"), 23000,       32000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(104,"Celia",to_date("19821024","YYYYMMDD"), 53000,       58000,        "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(105,"Robert",to_date("19840115","YYYYMMDD"), 31000,      36000,        "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(116,"Linda", to_date("19870730","YYYYMMDD"), 43000,       53000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(117,"David", to_date("19901231","YYYYMMDD"), 78000,       85000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(108,"Jode",  to_date("19960917","YYYYMMDD"), 21000,       29000,       "E")
  3  /
1 row created.
SQL>
SQL> -- prepare data for job table
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(101,   "Painter");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(122,   "Tester");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(123,   "Dediator");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(104,   "Chemist");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(105,   "Accountant");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(116,   "Manager");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(117,   "Programmer");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(108,   "Developer");
1 row created.
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
Hit a key to continue
     EMPNO ENAME      HIREDATE  ORIG_SALARY CURR_SALARY R
---------- ---------- --------- ----------- ----------- -
       122 Alison     21-MAR-96       45000       48000 E
       123 James      12-DEC-78       23000       32000 W
       104 Celia      24-OCT-82       53000       58000 E
       105 Robert     15-JAN-84       31000       36000 W
       116 Linda      30-JUL-87       43000       53000 E
       117 David      31-DEC-90       78000       85000 W
       108 Jode       17-SEP-96       21000       29000 E
7 rows selected.
SQL> select * from job;
Hit a key to continue
     EMPNO JOBTITLE
---------- ----------
       101 Painter
       122 Tester
       123 Dediator
       104 Chemist
       105 Accountant
       116 Manager
       117 Programmer
       108 Developer
8 rows selected.
SQL>
SQL>
SQL>
SQL> -- the query shows that the join is performed with the other WHERE conditions:
SQL>
SQL> SELECT e.empno, e.ename, j.jobtitle, e.orig_salary
  2  FROM employee e, job j
  3  WHERE e.orig_salary < 43000
  4    AND e.empno = j.empno;
Hit a key to continue
     EMPNO ENAME      JOBTITLE   ORIG_SALARY
---------- ---------- ---------- -----------
       123 James      Dediator         23000
       105 Robert     Accountant       31000
       108 Jode       Developer        21000
SQL>
SQL>
SQL>
SQL> drop table job;
Table dropped.
SQL>
SQL> -- clean the table
SQL> drop table Employee;
Table dropped.
SQL>
SQL>
SQL>



Used a GROUP BY in a query with no ordering or analytical function

   

SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    ename              VARCHAR2(10 BYTE),   -- Employee Name
  4    hireDate          DATE,                -- Date Employee Hired
  5    orig_salary        Number(8,2),         -- Orignal Salary
  6    curr_salary        Number(8,2),         -- Current Salary
  7    region             VARCHAR2(1 BYTE)     -- Region where employeed
  8  )
  9  /
Table created.
SQL>
SQL> create table job(
  2    empno              Number(3)  NOT NULL, -- Employee ID
  3    jobtitle           VARCHAR2(10 BYTE)    -- Employee job title
  4  )
  5  /
Table created.
SQL> -- prepare data for employee table
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(122,"Alison",to_date("19960321","YYYYMMDD"), 45000,       48000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(123, "James",to_date("19781212","YYYYMMDD"), 23000,       32000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(104,"Celia",to_date("19821024","YYYYMMDD"), 53000,       58000,        "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(105,"Robert",to_date("19840115","YYYYMMDD"), 31000,      36000,        "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(116,"Linda", to_date("19870730","YYYYMMDD"), 43000,       53000,       "E")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(117,"David", to_date("19901231","YYYYMMDD"), 78000,       85000,       "W")
  3  /
1 row created.
SQL> insert into Employee(empno,  ename,  hireDate,                       orig_salary, curr_salary, region)
  2                values(108,"Jode",  to_date("19960917","YYYYMMDD"), 21000,       29000,       "E")
  3  /
1 row created.
SQL>
SQL> -- prepare data for job table
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(101,   "Painter");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(122,   "Tester");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(123,   "Dediator");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(104,   "Chemist");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(105,   "Accountant");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(116,   "Manager");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(117,   "Programmer");
1 row created.
SQL>
SQL> insert into job(empno, jobtitle)
  2           values(108,   "Developer");
1 row created.
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
Hit a key to continue
     EMPNO ENAME      HIREDATE  ORIG_SALARY CURR_SALARY R
---------- ---------- --------- ----------- ----------- -
       122 Alison     21-MAR-96       45000       48000 E
       123 James      12-DEC-78       23000       32000 W
       104 Celia      24-OCT-82       53000       58000 E
       105 Robert     15-JAN-84       31000       36000 W
       116 Linda      30-JUL-87       43000       53000 E
       117 David      31-DEC-90       78000       85000 W
       108 Jode       17-SEP-96       21000       29000 E
7 rows selected.
SQL> select * from job;
Hit a key to continue
     EMPNO JOBTITLE
---------- ----------
       101 Painter
       122 Tester
       123 Dediator
       104 Chemist
       105 Accountant
       116 Manager
       117 Programmer
       108 Developer
8 rows selected.
SQL>
SQL>
SQL>
SQL> -- Used a GROUP BY in a query with no ordering or analytical function:
SQL>
SQL> SELECT j.jobtitle, COUNT(*), MAX(orig_salary) maxsalary,
  2    MIN(orig_salary) minsalary
  3  FROM employee e, job j
  4  WHERE e.orig_salary < 43000
  5    AND e.empno = j.empno
  6  GROUP BY j.jobtitle;
Hit a key to continue
JOBTITLE     COUNT(*)  MAXSALARY  MINSALARY
---------- ---------- ---------- ----------
Dediator            1      23000      23000
Accountant          1      31000      31000
Developer           1      21000      21000
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> drop table job;
Table dropped.
SQL>
SQL> -- clean the table
SQL> drop table Employee;
Table dropped.
SQL>
SQL>