MySQL中最簡單使用序列的方法就是使用 MySQL AUTO_INCREMENT 來定義列。
以下實例中創(chuàng)建了數(shù)據(jù)表insect, insect中id無需指定值可實現(xiàn)自動增長。
mysql> CREATE TABLE insect -> ( -> id INT UNSIGNED NOT NULL AUTO_INCREMENT, -> PRIMARY KEY (id), -> name VARCHAR(30) NOT NULL, # type of insect -> date DATE NOT NULL, # date collected -> origin VARCHAR(30) NOT NULL # where collected ); Query OK, 0 rows affected (0.02 sec) mysql> INSERT INTO insect (id,name,date,origin) VALUES -> (NULL,'housefly','2001-09-10','kitchen'), -> (NULL,'millipede','2001-09-10','driveway'), -> (NULL,'grasshopper','2001-09-10','front yard'); Query OK, 3 rows affected (0.02 sec) Records: 3 Duplicates: 0 Warnings: 0 mysql> SELECT * FROM insect ORDER BY id; +----+-------------+------------+------------+ | id | name | date | origin | +----+-------------+------------+------------+ | 1 | housefly | 2001-09-10 | kitchen | | 2 | millipede | 2001-09-10 | driveway | | 3 | grasshopper | 2001-09-10 | front yard | +----+-------------+------------+------------+ 3 rows in set (0.00 sec)
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