ORDER BY#

Оператор ORDER BY используется для сортировки вывода по определенному полю, по возрастанию или убыванию. Для этого он добавляется к оператору SELECT.

Если выполнить простой запрос SELECT, вывод будет таким:

new_db.db> SELECT * from switch;
+----------------+----------+------------+-------------------+------------+-----------+
| mac            | hostname | model      | location          | mngmt_ip   | mngmt_vid |
+----------------+----------+------------+-------------------+------------+-----------+
| 0010.D1DD.E1EE | sw1      | Cisco 3850 | London, Green Str | 10.255.1.1 | 255       |
| 0020.A2AA.C2CC | sw2      | Cisco 3850 | London, Green Str | 10.255.1.2 | 255       |
| 0040.A4AA.C2CC | sw4      | Cisco 3850 | London, Green Str | 10.255.1.4 | 255       |
| 0050.A5AA.C3CC | sw5      | Cisco 3850 | London, Green Str | 10.255.1.5 | 255       |
| 0060.A6AA.C4CC | sw6      | C3750      | London, Green Str | 10.255.1.6 | 255       |
| 0070.A7AA.C5CC | sw7      | Cisco 3650 | London, Green Str | 10.255.1.7 | 255       |
| 0030.A3AA.C1CC | sw3      | Cisco 3850 | London, Green Str | 10.255.1.3 | 255       |
+----------------+----------+------------+-------------------+------------+-----------+
7 rows in set
Time: 0.039s

С помощью оператора ORDER BY можно вывести записи в таблице switch, отсортировав их по имени коммутаторов:

new_db.db> SELECT * from switch ORDER BY hostname ASC;
+----------------+----------+------------+-------------------+------------+-----------+
| mac            | hostname | model      | location          | mngmt_ip   | mngmt_vid |
+----------------+----------+------------+-------------------+------------+-----------+
| 0010.D1DD.E1EE | sw1      | Cisco 3850 | London, Green Str | 10.255.1.1 | 255       |
| 0020.A2AA.C2CC | sw2      | Cisco 3850 | London, Green Str | 10.255.1.2 | 255       |
| 0030.A3AA.C1CC | sw3      | Cisco 3850 | London, Green Str | 10.255.1.3 | 255       |
| 0040.A4AA.C2CC | sw4      | Cisco 3850 | London, Green Str | 10.255.1.4 | 255       |
| 0050.A5AA.C3CC | sw5      | Cisco 3850 | London, Green Str | 10.255.1.5 | 255       |
| 0060.A6AA.C4CC | sw6      | C3750      | London, Green Str | 10.255.1.6 | 255       |
| 0070.A7AA.C5CC | sw7      | Cisco 3650 | London, Green Str | 10.255.1.7 | 255       |
+----------------+----------+------------+-------------------+------------+-----------+
7 rows in set
Time: 0.034s

По умолчанию сортировка выполняется по возрастанию, поэтому в запросе можно было не указывать параметр ASC:

new_db.db> SELECT * from switch ORDER BY hostname;
+----------------+----------+------------+-------------------+------------+-----------+
| mac            | hostname | model      | location          | mngmt_ip   | mngmt_vid |
+----------------+----------+------------+-------------------+------------+-----------+
| 0010.D1DD.E1EE | sw1      | Cisco 3850 | London, Green Str | 10.255.1.1 | 255       |
| 0020.A2AA.C2CC | sw2      | Cisco 3850 | London, Green Str | 10.255.1.2 | 255       |
| 0030.A3AA.C1CC | sw3      | Cisco 3850 | London, Green Str | 10.255.1.3 | 255       |
| 0040.A4AA.C2CC | sw4      | Cisco 3850 | London, Green Str | 10.255.1.4 | 255       |
| 0050.A5AA.C3CC | sw5      | Cisco 3850 | London, Green Str | 10.255.1.5 | 255       |
| 0060.A6AA.C4CC | sw6      | C3750      | London, Green Str | 10.255.1.6 | 255       |
| 0070.A7AA.C5CC | sw7      | Cisco 3650 | London, Green Str | 10.255.1.7 | 255       |
+----------------+----------+------------+-------------------+------------+-----------+
7 rows in set
Time: 0.034s

Сортировка по IP-адресу по убыванию:

SELECT * from switch ORDER BY mngmt_ip DESC;
+----------------+----------+------------+-------------------+------------+-----------+
| mac            | hostname | model      | location          | mngmt_ip   | mngmt_vid |
+----------------+----------+------------+-------------------+------------+-----------+
| 0070.A7AA.C5CC | sw7      | Cisco 3650 | London, Green Str | 10.255.1.7 | 255       |
| 0060.A6AA.C4CC | sw6      | C3750      | London, Green Str | 10.255.1.6 | 255       |
| 0050.A5AA.C3CC | sw5      | Cisco 3850 | London, Green Str | 10.255.1.5 | 255       |
| 0040.A4AA.C2CC | sw4      | Cisco 3850 | London, Green Str | 10.255.1.4 | 255       |
| 0030.A3AA.C1CC | sw3      | Cisco 3850 | London, Green Str | 10.255.1.3 | 255       |
| 0020.A2AA.C2CC | sw2      | Cisco 3850 | London, Green Str | 10.255.1.2 | 255       |
| 0010.D1DD.E1EE | sw1      | Cisco 3850 | London, Green Str | 10.255.1.1 | 255       |
+----------------+----------+------------+-------------------+------------+-----------+
7 rows in set
Time: 0.034s