MySQL 建表

Question

CREATE TABLE IF NOT EXISTS rr_category( cid TINYINT UNSIGNED AUTO_INCREMENT, c_name VARCHAR, parentid TINYINT UNSIGNED, PRIMARY KEY (cid) );报错怎么解决

Answer 1

TINYINT和VARCHAR后面都要加上长度，否则数据库不知道要怎么分配空间大小

Answer 2

你自己的语句：

mysql> CREATE TABLE IF NOT EXISTS rr_category( cid TINYINT UNSIGNED AUTO_INCREMENT, c_name VARCHAR, parentid TINYINT UNSIGNED, PRIMARY KEY (cid) );

执行后报这个错误：

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' parentid TINYINT UNSIGNED, PRIMARY KEY (cid) )' at line 1

修改后的语句(采取“Hadooper”的提示)：

mysql> CREATE TABLE IF NOT EXISTS rr_category( cid TINYINT UNSIGNED AUTO_INCREMENT, c_name VARCHAR(20), parentid TINYINT UNSIGNED, PRIMARY KEY (cid) );

执行后的提示：

Query OK, 0 rows affected

查看结果：

mysql> show tables;

+----------------+

| Tables_in_test |

+----------------+

| rr_category    |

| users          |

+----------------+

6 rows in set

Answer 3

 IF NOT  应该是  inot

Answer 4

你把报错的提示发出来啊  这样不好看呢! 看提示就知道了