Oracle PL/SQL Tutorial/Query Select/Order By

Материал из SQL эксперт
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Add aggregate function in order by clause

SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL primary key,
  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    1234.56 Toronto    Programmer
02   Alison               Mathews              21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James                Smith                12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia                Rice                 24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert               Black                15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda                Green                30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David                Larry                31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James                Cat                  17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> select CITY, avg(salary) avg_salary
  2  from employee
  3  group by CITY
  4  order by avg(salary) desc;

CITY       AVG_SALARY
---------- ----------
New York      6110.28
Vancouver     3823.78
Toronto       1234.56
3 rows selected.
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>
SQL>


A SELECT with Ordering

The ordering is applied to the result set after the result is established:



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    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> SELECT id, first_name, salary FROM employee ORDER BY salary
  2  /
ID   FIRST_NAME     SALARY
---- ---------- ----------
08   James         1232.78
01   Jason         1234.56
05   Robert        2334.78
04   Celia         2344.78
06   Linda         4322.78
03   James         6544.78
02   Alison        6661.78
07   David         7897.78
8 rows selected.
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>
SQL>
SQL>


Combine order by clause with case statement

SQL>
SQL>
SQL> create table employees(
  2    empno      NUMBER(4)
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , msal       NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2) ) ;
Table created.
SQL>
SQL>
SQL> insert into employees values(1,"Jason",  "N",  "TRAINER", 2,   date "1965-12-18",  800 , NULL,  10);
1 row created.
SQL> insert into employees values(2,"Jerry",  "J",  "SALESREP",3,   date "1966-11-19",  1600, 300,   10);
1 row created.
SQL> insert into employees values(3,"Jord",   "T" , "SALESREP",4,   date "1967-10-21",  1700, 500,   20);
1 row created.
SQL> insert into employees values(4,"Mary",   "J",  "MANAGER", 5,   date "1968-09-22",  1800, NULL,  20);
1 row created.
SQL> insert into employees values(5,"Joe",    "P",  "SALESREP",6,   date "1969-08-23",  1900, 1400,  30);
1 row created.
SQL> insert into employees values(6,"Black",  "R",  "MANAGER", 7,   date "1970-07-24",  2000, NULL,  30);
1 row created.
SQL> insert into employees values(7,"Red",    "A",  "MANAGER", 8,   date "1971-06-25",  2100, NULL,  40);
1 row created.
SQL> insert into employees values(8,"White",  "S",  "TRAINER", 9,   date "1972-05-26",  2200, NULL,  40);
1 row created.
SQL> insert into employees values(9,"Yellow", "C",  "DIRECTOR",10,  date "1973-04-27",  2300, NULL,  20);
1 row created.
SQL> insert into employees values(10,"Pink",  "J",  "SALESREP",null,date "1974-03-28",  2400, 0,     30);
1 row created.
SQL>
SQL>
SQL> select job, ename
  2  ,      case
  3           when msal <= 2500
  4           then "cheap"
  5           else "expensive"
  6         end         as class
  7  from   employees
  8  where  bdate < date "1964-01-01"
  9  order  by case job
 10            when "DIRECTOR" then 1
 11            when "MANAGER"  then 2
 12                            else 3
 13            end;
no rows selected
SQL>
SQL> drop table employees;
Table dropped.


Order by a calculated column

SQL>
SQL> CREATE TABLE titles(
  2    title_id   CHAR(3)      NOT NULL,
  3    title_name VARCHAR(40)  NOT NULL,
  4    type       VARCHAR(10)  NULL    ,
  5    pub_id     CHAR(3)      NOT NULL,
  6    pages      INTEGER      NULL    ,
  7    price      DECIMAL(5,2) NULL    ,
  8    sales      INTEGER      NULL    ,
  9    pubdate    DATE         NULL    ,
 10    contract   SMALLINT     NOT NULL
 11  );
Table created.
SQL>
SQL>
SQL>
SQL>
SQL> INSERT INTO titles VALUES("T01","Java","history","P01",111,21.99,566,DATE "2000-08-01",1);
1 row created.
SQL> INSERT INTO titles VALUES("T02","Oracle","history","P03", 114,19.95,9566,DATE "1998-04-01",1);
1 row created.
SQL> INSERT INTO titles VALUES("T03","SQL","computer","P02", 122,39.95,25667,DATE "2000-09-01",1);
1 row created.
SQL> INSERT INTO titles VALUES("T04","C++","psychology","P04", 511,12.99,13001,DATE "1999-05-31",1);
1 row created.
SQL> INSERT INTO titles VALUES("T05","Python","psychology","P04", 101,6.95,201440,DATE "2001-01-01",1);
1 row created.
SQL> INSERT INTO titles VALUES("T06","JavaScript","biography","P01", 173,19.95,11320,DATE "2000-07-31",1);
1 row created.
SQL> INSERT INTO titles VALUES("T07","LINQ","biography","P03", 331,23.95,1500200,DATE "1999-10-01",1);
1 row created.
SQL> INSERT INTO titles VALUES("T08","C#","children","P04", 861,10.00,4095,DATE "2001-06-01",1);
1 row created.
SQL> INSERT INTO titles VALUES("T09","SQL Server","children","P04", 212,13.95,5000,DATE "2002-05-31",1);
1 row created.
SQL> INSERT INTO titles VALUES("T10","AJAX","biography","P01", NULL,NULL,NULL,NULL,0);
1 row created.
SQL> INSERT INTO titles VALUES("T11","VB","psychology","P04", 821,7.99,94123,DATE "2000-11-30",1);
1 row created.
SQL> INSERT INTO titles VALUES("T12","Office","biography","P01", 507,12.99,100001,DATE "2000-08-31",1);
1 row created.
SQL> INSERT INTO titles VALUES("T13","VBA","history","P03", 812,29.99,10467,DATE "1999-05-31",1);
1 row created.
SQL>
SQL>
SQL>
SQL>
SQL> SELECT title_id,
  2         price,
  3         sales,
  4         price * sales AS "Revenue"
  5    FROM titles
  6    ORDER BY "Revenue" DESC;
TIT      PRICE      SALES    Revenue
--- ---------- ---------- ----------
T10
T07      23.95    1500200   35929790
T05       6.95     201440    1400008
T12      12.99     100001 1299012.99
T03      39.95      25667 1025396.65
T11       7.99      94123  752042.77
T13      29.99      10467  313905.33
T06      19.95      11320     225834
T02      19.95       9566   190841.7
T04      12.99      13001  168882.99
T09      13.95       5000      69750
TIT      PRICE      SALES    Revenue
--- ---------- ---------- ----------
T08         10       4095      40950
T01      21.99        566   12446.34
13 rows selected.
SQL>
SQL> drop table titles;
Table dropped.
SQL>
SQL>


Order by two columns

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    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL> SELECT * FROM employee ORDER BY start_date, first_name;

ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.


Order by username

SQL>
SQL>
SQL> SELECT username, default_tablespace
  2  FROM dba_users
  3  where rownum < 50
  4  ORDER BY username desc;
USERNAME                       DEFAULT_TABLESPACE
------------------------------ ------------------------------
XDB                            SYSAUX
TSMSYS                         SYSTEM
SYSTEM                         SYSTEM
SYS                            SYSTEM
PLSQL                          USERS
OUTLN                          SYSTEM
MDSYS                          SYSTEM
sqle                         SYSTEM
HR                             USERS
FLOWS_FILES                    SYSAUX
FLOWS_020100                   SYSAUX
DIP                            SYSTEM
DBSNMP                         SYSAUX
CTXSYS                         SYSAUX
ANONYMOUS                      SYSAUX
15 rows selected.


Order the table on the employee"s original salary (orig_salary)

SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE)
  8  )
  9  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,
        "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,
        "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,
        "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (4,      "Tom",   to_date("20060913","YYYYMMDD"), 2413,              6787,
        "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (5,      "Jane",  to_date("20050417","YYYYMMDD"), 7654,              4345,
        "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (6,      "James", to_date("20040718","YYYYMMDD"), 5679,              6546,
        "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (7,      "Jodd",  to_date("20030720","YYYYMMDD"), 5438,              7658,
        "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (8,      "Joke",  to_date("20020101","YYYYMMDD"), 8765,              4543,
        "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_S
ALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,
        "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         3 Joe             25-JAN-86        4321        5654 E
         4 Tom             13-SEP-06        2413        6787 W
         5 Jane            17-APR-05        7654        4345 E
         6 James           18-JUL-04        5679        6546 W
         7 Jodd            20-JUL-03        5438        7658 E
         8 Joke            01-JAN-02        8765        4543 W
         9 Jack            29-AUG-01        7896        1232 E
9 rows selected.
SQL>
SQL>
SQL> SELECT * FROM employee ORDER BY orig_salary
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         4 Tom             13-SEP-06        2413        6787 W
         3 Joe             25-JAN-86        4321        5654 E
         7 Jodd            20-JUL-03        5438        7658 E
         6 James           18-JUL-04        5679        6546 W
         5 Jane            17-APR-05        7654        4345 E
         9 Jack            29-AUG-01        7896        1232 E
         8 Joke            01-JAN-02        8765        4543 W
9 rows selected.
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>


Order Your Email

SQL>
SQL> CREATE TABLE email (e   VARCHAR(50));
Table created.
SQL> INSERT INTO email VALUES ("I@napier.ac.uk");
1 row created.
SQL> INSERT INTO email VALUES ("P.Bhardwaj@napier.ac.uk");
1 row created.
SQL> INSERT INTO email VALUES ("Scott@rbs.co.uk");
1 row created.
SQL> INSERT INTO email VALUES ("Alan@rbs.co.uk");
1 row created.
SQL> INSERT INTO email VALUES ("abc@s.ru");
1 row created.
SQL>
SQL> SELECT SUBSTR(e,1+INSTR(e,".",-1)),e
  2    FROM email;
SUBSTR(E,1+INSTR(E,".",-1))
--------------------------------------------------
E
--------------------------------------------------
uk
I@napier.ac.uk
uk
P.Bhardwaj@napier.ac.uk
uk
Scott@rbs.co.uk

SUBSTR(E,1+INSTR(E,".",-1))
--------------------------------------------------
E
--------------------------------------------------
uk
Alan@rbs.co.uk
com
abc@s.ru

SQL>
SQL> DROP TABLE email;
Table dropped.
SQL>


Reference alias name in order by clause

SQL>
SQL>
SQL> CREATE TABLE employees (
  2    au_id    CHAR(3)     NOT NULL,
  3    au_fname VARCHAR(15) NOT NULL,
  4    au_lname VARCHAR(15) NOT NULL,
  5    phone    VARCHAR(12) NULL    ,
  6    address  VARCHAR(20) NULL    ,
  7    city     VARCHAR(15) NULL    ,
  8    state    CHAR(2)     NULL    ,
  9    zip      CHAR(5)     NULL
 10  );
Table created.
SQL>
SQL> INSERT INTO employees VALUES("A01","S","B","111-111-1111","75 St","Boston","NY","11111");
1 row created.
SQL> INSERT INTO employees VALUES("A02","W","H","222-222-2222","2922 Rd","Boston","CO","22222");
1 row created.
SQL> INSERT INTO employees VALUES("A03","H","H","333-333-3333","3800 Ave, #14F","San Francisco","CA","33333");
1 row created.
SQL> INSERT INTO employees VALUES("A04","K","H","444-444-4444","3800 Ave, #14F","San Francisco","CA","44444");
1 row created.
SQL> INSERT INTO employees VALUES("A05","C","K","555-555-5555","114 St","New York","NY","55555");
1 row created.
SQL> INSERT INTO employees VALUES("A06"," ","K","666-666-666","390 Mall","Palo Alto","CA","66666");
1 row created.
SQL> INSERT INTO employees VALUES("A07","P","O","777-777-7777","1442 St","Sarasota","FL","77777");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT au_fname AS "First name",
  2         au_lname AS "Last name",
  3         state
  4    FROM employees
  5    ORDER BY state        ASC,
  6             "Last name"  ASC,
  7             "First name" ASC;
First name      Last name       ST
--------------- --------------- --
H               H               CA
K               H               CA
                K               CA
W               H               CO
P               O               FL
S               B               NY
C               K               NY
7 rows selected.
SQL>
SQL>
SQL> drop table employees;
Table dropped.


Sort by index ascending and descending

SQL>
SQL>
SQL> CREATE TABLE employees (
  2    au_id    CHAR(3)     NOT NULL,
  3    au_fname VARCHAR(15) NOT NULL,
  4    au_lname VARCHAR(15) NOT NULL,
  5    phone    VARCHAR(12) NULL    ,
  6    address  VARCHAR(20) NULL    ,
  7    city     VARCHAR(15) NULL    ,
  8    state    CHAR(2)     NULL    ,
  9    zip      CHAR(5)     NULL
 10  );
Table created.
SQL>
SQL> INSERT INTO employees VALUES("A01","S","B","111-111-1111","75 St","Boston","NY","11111");
1 row created.
SQL> INSERT INTO employees VALUES("A02","W","H","222-222-2222","2922 Rd","Boston","CO","22222");
1 row created.
SQL> INSERT INTO employees VALUES("A03","H","H","333-333-3333","3800 Ave, #14F","San Francisco","CA","33333");
1 row created.
SQL> INSERT INTO employees VALUES("A04","K","H","444-444-4444","3800 Ave, #14F","San Francisco","CA","44444");
1 row created.
SQL> INSERT INTO employees VALUES("A05","C","K","555-555-5555","114 St","New York","NY","55555");
1 row created.
SQL> INSERT INTO employees VALUES("A06"," ","K","666-666-666","390 Mall","Palo Alto","CA","66666");
1 row created.
SQL> INSERT INTO employees VALUES("A07","P","O","777-777-7777","1442 St","Sarasota","FL","77777");
1 row created.
SQL>
SQL>
SQL> SELECT au_fname, au_lname, city, state
  2    FROM employees
  3    ORDER BY 4 ASC, 2 DESC;
AU_FNAME        AU_LNAME        CITY            ST
--------------- --------------- --------------- --
                K               Palo Alto       CA
K               H               San Francisco   CA
H               H               San Francisco   CA
W               H               Boston          CO
P               O               Sarasota        FL
C               K               New York        NY
S               B               Boston          NY
7 rows selected.
SQL>
SQL>
SQL> drop table employees;
Table dropped.


Sorting Rows Using the ORDER BY Clause

ORDER BY clause sorts the rows.

The ORDER BY clause may specify one or more columns on which to sort the data

The ORDER BY must follow the FROM clause or the WHERE clause (if a WHERE clause is supplied).

The following example uses the ORDER BY clause to sort the last_name column values:



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    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL> SELECT * FROM employee ORDER BY last_name;
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>


Sort last name ascending

SQL>
SQL>
SQL> CREATE TABLE employees (
  2    au_id    CHAR(3)     NOT NULL,
  3    au_fname VARCHAR(15) NOT NULL,
  4    au_lname VARCHAR(15) NOT NULL,
  5    phone    VARCHAR(12) NULL    ,
  6    address  VARCHAR(20) NULL    ,
  7    city     VARCHAR(15) NULL    ,
  8    state    CHAR(2)     NULL    ,
  9    zip      CHAR(5)     NULL
 10  );
Table created.
SQL>
SQL> INSERT INTO employees VALUES("A01","S","B","111-111-1111","75 St","Boston","NY","11111");
1 row created.
SQL> INSERT INTO employees VALUES("A02","W","H","222-222-2222","2922 Rd","Boston","CO","22222");
1 row created.
SQL> INSERT INTO employees VALUES("A03","H","H","333-333-3333","3800 Ave, #14F","San Francisco","CA","33333");
1 row created.
SQL> INSERT INTO employees VALUES("A04","K","H","444-444-4444","3800 Ave, #14F","San Francisco","CA","44444");
1 row created.
SQL> INSERT INTO employees VALUES("A05","C","K","555-555-5555","114 St","New York","NY","55555");
1 row created.
SQL> INSERT INTO employees VALUES("A06"," ","K","666-666-666","390 Mall","Palo Alto","CA","66666");
1 row created.
SQL> INSERT INTO employees VALUES("A07","P","O","777-777-7777","1442 St","Sarasota","FL","77777");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT au_fname, au_lname, city, state
  2    FROM employees
  3    ORDER BY au_lname ASC;
AU_FNAME        AU_LNAME        CITY            ST
--------------- --------------- --------------- --
S               B               Boston          NY
H               H               San Francisco   CA
W               H               Boston          CO
K               H               San Francisco   CA
C               K               New York        NY
                K               Palo Alto       CA
P               O               Sarasota        FL
7 rows selected.
SQL>
SQL>
SQL> drop table employees;
Table dropped.


Sort last name descending

SQL>
SQL>
SQL> CREATE TABLE employees (
  2    au_id    CHAR(3)     NOT NULL,
  3    au_fname VARCHAR(15) NOT NULL,
  4    au_lname VARCHAR(15) NOT NULL,
  5    phone    VARCHAR(12) NULL    ,
  6    address  VARCHAR(20) NULL    ,
  7    city     VARCHAR(15) NULL    ,
  8    state    CHAR(2)     NULL    ,
  9    zip      CHAR(5)     NULL
 10  );
Table created.
SQL>
SQL> INSERT INTO employees VALUES("A01","S","B","111-111-1111","75 St","Boston","NY","11111");
1 row created.
SQL> INSERT INTO employees VALUES("A02","W","H","222-222-2222","2922 Rd","Boston","CO","22222");
1 row created.
SQL> INSERT INTO employees VALUES("A03","H","H","333-333-3333","3800 Ave, #14F","San Francisco","CA","33333");
1 row created.
SQL> INSERT INTO employees VALUES("A04","K","H","444-444-4444","3800 Ave, #14F","San Francisco","CA","44444");
1 row created.
SQL> INSERT INTO employees VALUES("A05","C","K","555-555-5555","114 St","New York","NY","55555");
1 row created.
SQL> INSERT INTO employees VALUES("A06"," ","K","666-666-666","390 Mall","Palo Alto","CA","66666");
1 row created.
SQL> INSERT INTO employees VALUES("A07","P","O","777-777-7777","1442 St","Sarasota","FL","77777");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT au_fname, au_lname, city, state
  2    FROM employees
  3    ORDER BY au_fname DESC;
AU_FNAME        AU_LNAME        CITY            ST
--------------- --------------- --------------- --
W               H               Boston          CO
S               B               Boston          NY
P               O               Sarasota        FL
K               H               San Francisco   CA
H               H               San Francisco   CA
C               K               New York        NY
                K               Palo Alto       CA
7 rows selected.
SQL>
SQL>
SQL>
SQL> drop table employees;
Table dropped.


Sort one column ascending and another column descending

SQL>
SQL>
SQL> CREATE TABLE employees (
  2    au_id    CHAR(3)     NOT NULL,
  3    au_fname VARCHAR(15) NOT NULL,
  4    au_lname VARCHAR(15) NOT NULL,
  5    phone    VARCHAR(12) NULL    ,
  6    address  VARCHAR(20) NULL    ,
  7    city     VARCHAR(15) NULL    ,
  8    state    CHAR(2)     NULL    ,
  9    zip      CHAR(5)     NULL
 10  );
Table created.
SQL>
SQL> INSERT INTO employees VALUES("A01","S","B","111-111-1111","75 St","Boston","NY","11111");
1 row created.
SQL> INSERT INTO employees VALUES("A02","W","H","222-222-2222","2922 Rd","Boston","CO","22222");
1 row created.
SQL> INSERT INTO employees VALUES("A03","H","H","333-333-3333","3800 Ave, #14F","San Francisco","CA","33333");
1 row created.
SQL> INSERT INTO employees VALUES("A04","K","H","444-444-4444","3800 Ave, #14F","San Francisco","CA","44444");
1 row created.
SQL> INSERT INTO employees VALUES("A05","C","K","555-555-5555","114 St","New York","NY","55555");
1 row created.
SQL> INSERT INTO employees VALUES("A06"," ","K","666-666-666","390 Mall","Palo Alto","CA","66666");
1 row created.
SQL> INSERT INTO employees VALUES("A07","P","O","777-777-7777","1442 St","Sarasota","FL","77777");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT au_fname, au_lname, city, state
  2    FROM employees
  3    ORDER BY state ASC,
  4             city  DESC;
AU_FNAME        AU_LNAME        CITY            ST
--------------- --------------- --------------- --
K               H               San Francisco   CA
H               H               San Francisco   CA
                K               Palo Alto       CA
W               H               Boston          CO
P               O               Sarasota        FL
C               K               New York        NY
S               B               Boston          NY
7 rows selected.
SQL>
SQL> drop table employees;
Table dropped.


Sort the rows by descending order with DESC appended to order by clause

By default, the ORDER BY clause sorts the columns in ascending order.

In ascending order, lower values appear first.

You can use the DESC keyword to sort the columns in descending order.

In descending order, higher values appear first.

You can also use the ASC keyword to explicitly specify an ascending sort.



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    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL> SELECT * FROM employee ORDER BY last_name Desc;
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.


Sort two columns with different ordering

The following example uses the ORDER BY clause to sort the first_name column values in ascending order, followed by a sort on the last_name column values in descending order:



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    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> SELECT * FROM employee ORDER BY first_name ASC, last_name DESC;
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>


Use a column position number in the ORDER BY clause

Use a column position number in the ORDER BY clause to indicate which column to sort.

1 means sort by the first column selected, 2 means sort by the second column, and so on.



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    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL>
SQL> SELECT id, first_name, last_name FROM employee ORDER BY 2;
ID   FIRST_NAME LAST_NAME
---- ---------- ----------
02   Alison     Mathews
04   Celia      Rice
07   David      Larry
03   James      Smith
08   James      Cat
01   Jason      Martin
06   Linda      Green
05   Robert     Black
8 rows selected.
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>