mysql查询中Limit、order的简单示例

/*
mysql> Drop table Item;
Query OK, 0 rows affected (0.01 sec)

mysql> CREATE TABLE Item
    -> (
    ->    ID SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
    ->    Name VARCHAR(50) NOT NULL,
    ->    InStock SMALLINT UNSIGNED NOT NULL,
    ->    OnOrder SMALLINT UNSIGNED NOT NULL,
    ->    Reserved SMALLINT UNSIGNED NOT NULL,
    ->    Department ENUM('Classical', 'Popular') NOT NULL,
    ->    Category VARCHAR(20) NOT NULL,
    ->    RowUpdate TIMESTAMP NOT NULL
    -> );
Query OK, 0 rows affected (0.05 sec)

mysql> INSERT INTO Item (Name, InStock, OnOrder, Reserved, Department, Category)

    ->           VALUES ('Bloodshot',      10,      5,       1, 'Popular',
'Rock'),
    ->                  ('Most',           10,      5,       2, 'Classical',
'Opera'),
    ->                  ('Jazz',           17,      4,       3, 'Popular',
'Jazz'),
    ->                  ('Class',           9,      4,       4, 'Classical',
'Dance'),
    ->                  ('Violin',         24,      2,       5, 'Classical',
'General'),
    ->                  ('Cha Cha',        16,      6,       6, 'Classical',
'Vocal'),
    ->                  ('Blues',           2,     25,       7, 'Popular',
'Blues'),
    ->                  ('Pure',           32,      3,      18, 'Popular',
'Jazz'),
    ->                  ('Mud',            12,     15,      19, 'Popular',
'Country'),
    ->                  ('The',             5,     20,      11, 'Popular',
'New Age'),
    ->                  ('Embrace',        24,     11,      12, 'Popular',
'New Age'),
    ->                  ('Magic',          42,     17,      13, 'Classical',
'General'),
    ->                  ('Lake',           25,     44,      24, 'Classical',
'Dance'),
    ->                  ('LaLala',         20,     10,       5, 'Classical',
'Opera'),
    ->                  ('Soul',           15,     30,      16, 'Popular',
'Blues'),
    ->                  ('Stages',         42,      0,       7, 'Popular',
'Blues'),
    ->                  ('Six',            16,      8,       6, 'Classical',
'General');
Query OK, 17 rows affected (0.00 sec)
Records: 17  Duplicates: 0  Warnings: 0

mysql> select * from Item;
+----+-----------+---------+---------+----------+------------+----------+---------------------+
| ID | Name      | InStock | OnOrder | Reserved | Department | Category | RowUpdate           |
+----+-----------+---------+---------+----------+------------+----------+---------------------+
|  1 | Bloodshot |      10 |       5 |        1 | Popular    | Rock     | 2005-10-09 09:19:50 |
|  2 | Most      |      10 |       5 |        2 | Classical  | Opera    | 2005-10-09 09:19:50 |
|  3 | Jazz      |      17 |       4 |        3 | Popular    | Jazz     | 2005-10-09 09:19:50 |
|  4 | Class     |       9 |       4 |        4 | Classical  | Dance    | 2005-10-09 09:19:50 |
|  5 | Violin    |      24 |       2 |        5 | Classical  | General  | 2005-10-09 09:19:50 |
|  6 | Cha Cha   |      16 |       6 |        6 | Classical  | Vocal    | 2005-10-09 09:19:50 |
|  7 | Blues     |       2 |      25 |        7 | Popular    | Blues    | 2005-10-09 09:19:50 |
|  8 | Pure      |      32 |       3 |       18 | Popular    | Jazz     | 2005-10-09 09:19:50 |
|  9 | Mud       |      12 |      15 |       19 | Popular    | Country  | 2005-10-09 09:19:50 |
| 10 | The       |       5 |      20 |       11 | Popular    | New Age  | 2005-10-09 09:19:50 |
| 11 | Embrace   |      24 |      11 |       12 | Popular    | New Age  | 2005-10-09 09:19:50 |
| 12 | Magic     |      42 |      17 |       13 | Classical  | General  | 2005-10-09 09:19:50 |
| 13 | Lake      |      25 |      44 |       24 | Classical  | Dance    | 2005-10-09 09:19:50 |
| 14 | LaLala    |      20 |      10 |        5 | Classical  | Opera    | 2005-10-09 09:19:50 |
| 15 | Soul      |      15 |      30 |       16 | Popular    | Blues    | 2005-10-09 09:19:50 |
| 16 | Stages    |      42 |       0 |        7 | Popular    | Blues    | 2005-10-09 09:19:50 |
| 17 | Six       |      16 |       8 |        6 | Classical  | General  | 2005-10-09 09:19:50 |
+----+-----------+---------+---------+----------+------------+----------+---------------------+
17 rows in set (0.00 sec)

mysql> SELECT ID, Name, InStock
    -> FROM Item
    -> WHERE Department='Classical'
    -> ORDER BY ID DESC
    -> LIMIT 3,4;
+----+---------+---------+
| ID | Name    | InStock |
+----+---------+---------+
| 12 | Magic   |      42 |
|  6 | Cha Cha |      16 |
|  5 | Violin  |      24 |
|  4 | Class   |       9 |
+----+---------+---------+
4 rows in set (0.00 sec)

*/

Drop table Item;

CREATE TABLE Item
(
   ID SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
   Name VARCHAR(50) NOT NULL,
   InStock SMALLINT UNSIGNED NOT NULL,
   OnOrder SMALLINT UNSIGNED NOT NULL,
   Reserved SMALLINT UNSIGNED NOT NULL,
   Department ENUM('Classical', 'Popular') NOT NULL,
   Category VARCHAR(20) NOT NULL,
   RowUpdate TIMESTAMP NOT NULL
);

INSERT INTO Item (Name, InStock, OnOrder, Reserved, Department, Category)
          VALUES ('Bloodshot',      10,      5,       1, 'Popular',      'Rock'),
                 ('Most',           10,      5,       2, 'Classical',    'Opera'),
                 ('Jazz',           17,      4,       3, 'Popular',      'Jazz'),
                 ('Class',           9,      4,       4, 'Classical',    'Dance'),
                 ('Violin',         24,      2,       5, 'Classical',    'General'),
                 ('Cha Cha',        16,      6,       6, 'Classical',    'Vocal'),
                 ('Blues',           2,     25,       7, 'Popular',      'Blues'),
                 ('Pure',           32,      3,      18, 'Popular',      'Jazz'),
                 ('Mud',            12,     15,      19, 'Popular',      'Country'),
                 ('The',             5,     20,      11, 'Popular',      'New Age'),
                 ('Embrace',        24,     11,      12, 'Popular',      'New Age'),
                 ('Magic',          42,     17,      13, 'Classical',    'General'),
                 ('Lake',           25,     44,      24, 'Classical',    'Dance'),
                 ('LaLala',         20,     10,       5, 'Classical',    'Opera'),
                 ('Soul',           15,     30,      16, 'Popular',      'Blues'),
                 ('Stages',         42,      0,       7, 'Popular',      'Blues'),
                 ('Six',            16,      8,       6, 'Classical',    'General');

select * from Item;

SELECT ID, Name, InStock
FROM Item
WHERE Department='Classical'
ORDER BY ID DESC
LIMIT 3,4;