Oracle PL/SQL/Analytical Functions/Top Values

The top five salaries

SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  3    First_Name         VARCHAR2(20 BYTE),
  4    Last_Name          VARCHAR2(20 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(20 BYTE),
  9    Description        VARCHAR2(80 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"), 2234.78, "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"), 2324.78, "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"), 3334.78, "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"), 4334.78, "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"), 5334.78,"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"), 6334.78,"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"), 7334.78,"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    1234.56 Toronto              Programmer
02   Alison               Mathews              21-MAR-76 21-FEB-86    2234.78 Vancouver            Tester
03   James                Smith                12-DEC-78 15-MAR-90    2324.78 Vancouver            Tester
04   Celia                Rice                 24-OCT-82 21-APR-99    3334.78 Vancouver            Manager
05   Robert               Black                15-JAN-84 08-AUG-98    4334.78 Vancouver            Tester
06   Linda                Green                30-JUL-87 04-JAN-96    5334.78 New York             Tester
07   David                Larry                31-DEC-90 12-FEB-98    6334.78 New York             Manager
08   James                Cat                  17-SEP-96 15-APR-02    7334.78 Vancouver            Tester
8 rows selected.
SQL>
SQL>
SQL> -- the top five salaries
SQL>
SQL> SELECT * FROM
  2  (SELECT id, first_name, salary, DENSE_RANK() OVER(ORDER BY salary desc) toprank
  3  FROM employee)
  4  WHERE toprank <= 5;
ID   FIRST_NAME               SALARY    TOPRANK
---- -------------------- ---------- ----------
08   James                   7334.78          1
07   David                   6334.78          2
06   Linda                   5334.78          3
05   Robert                  4334.78          4
04   Celia                   3334.78          5
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>
SQL>
SQL>