如何按MySQL中的自動遞增排序?
我們首先建立一個表格 −
mysql> create table DemoTable(Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,FirstName varchar(100)); Query OK, 0 rows affected (0.70 sec)
使用insert命令在表中插入一些記錄 −
mysql> insert into DemoTable(FirstName) values('Chris'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable(FirstName) values('Robert'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable(FirstName) values('David'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable(FirstName) values('Mike'); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable(FirstName) values('Adam'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable(FirstName) values('Carol'); Query OK, 1 row affected (0.12 sec)
使用select語句在表中顯示所有記錄 −
mysql> select *from DemoTable;
這將生成以下輸出 −
+----+-----------+ | Id | FirstName | +----+-----------+ | 1 | Chris | | 2 | Robert | | 3 | David | | 4 | Mike | | 5 | Adam | | 6 Carol | +----+-----------+ 6 rows in set (0.00 sec)
以下是按自動遞增排序的查詢 −
mysql> select *from DemoTable order by Id DESC;
這將生成以下輸出 −
+----+-----------+ | Id | FirstName | +----+-----------+ | 6 | Carol | | 5 | Adam | | 4 | Mike | | 3 | David | | 2 | Robert | | 1 | Chris | +----+-----------+ 6 rows in set (0.00 sec)
廣告