Use COUNT and GROUP : Count : Select Clause SQL / MySQL


SQL / MySQL » Select Clause » Count »

 

Use COUNT and GROUP



/*

mysql> select * from Item;
+----+-----------+---------+---------+----------+------------+----------+---------------------+
| ID | Name      | InStock | OnOrder | Reserved | Department | Category | RowUpdate           |
+----+-----------+---------+---------+----------+------------+----------+---------------------+
|  1 | Bloodshot |      10 |       5 |        1 | Popular    | Rock     | 2005-10-09 09:19:44 |
|  2 | Most      |      10 |       5 |        2 | Classical  | Opera    | 2005-10-09 09:19:44 |
|  3 | Jazz      |      17 |       4 |        3 | Popular    | Jazz     | 2005-10-09 09:19:44 |
|  4 | Class     |       9 |       4 |        4 | Classical  | Dance    | 2005-10-09 09:19:44 |
|  5 | Violin    |      24 |       2 |        5 | Classical  | General  | 2005-10-09 09:19:44 |
|  6 | Cha Cha   |      16 |       6 |        6 | Classical  | Vocal    | 2005-10-09 09:19:44 |
|  7 | Blues     |       2 |      25 |        7 | Popular    | Blues    | 2005-10-09 09:19:44 |
|  8 | Pure      |      32 |       3 |       18 | Popular    | Jazz     | 2005-10-09 09:19:44 |
|  9 | Mud       |      12 |      15 |       19 | Popular    | Country  | 2005-10-09 09:19:44 |
| 10 | The       |       5 |      20 |       11 | Popular    | New Age  | 2005-10-09 09:19:44 |
| 11 | Embrace   |      24 |      11 |       12 | Popular    | New Age  | 2005-10-09 09:19:44 |
| 12 | Magic     |      42 |      17 |       13 | Classical  | General  | 2005-10-09 09:19:44 |
| 13 | Lake      |      25 |      44 |       24 | Classical  | Dance    | 2005-10-09 09:19:44 |
| 14 | LaLala    |      20 |      10 |        5 | Classical  | Opera    | 2005-10-09 09:19:44 |
| 15 | Soul      |      15 |      30 |       16 | Popular    | Blues    | 2005-10-09 09:19:44 |
| 16 | Stages    |      42 |       0 |        7 | Popular    | Blues    | 2005-10-09 09:19:44 |
| 17 | Six       |      16 |       8 |        6 | Classical  | General  | 2005-10-09 09:19:44 |
+----+-----------+---------+---------+----------+------------+----------+---------------------+
17 rows in set (0.03 sec)

mysql> SELECT Category, COUNT(*) AS Total
    -> FROM Item
    -> WHERE Department='Popular'
    -> GROUP BY Category;
+----------+-------+
| Category | Total |
+----------+-------+
| Blues    |     3 |
| Country  |     1 |
| Jazz     |     2 |
| New Age  |     2 |
| Rock     |     1 |
+----------+-------+
5 rows in set (0.02 sec)

*/

Drop table Item;

CREATE TABLE Item
(
   ID SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
   Name VARCHAR(50NOT NULL,
   InStock SMALLINT UNSIGNED NOT NULL,
   OnOrder SMALLINT UNSIGNED NOT NULL,
   Reserved SMALLINT UNSIGNED NOT NULL,
   Department ENUM('Classical', 'Popular') NOT NULL,
   Category VARCHAR(20NOT 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 Category, COUNT(*AS Total
FROM Item
WHERE Department='Popular'
GROUP BY Category;



           
       



Leave a Comment / Note


 
Verification is used to prevent unwanted posts (spam). .

Follow Navioo On Twitter

SQL / MySQL

 Navioo Select Clause
» Count