MySQL創建另一個主鍵

Question

我嘗試爲文章材料創建最簡單的表，但MySQL爲我創建了另一個不需要的主鍵。

$command = "CREATE TABLE IF NOT EXISTS `$this->table` (
      `id` int unsigned UNIQUE NOT NULL AUTO_INCREMENT PRIMARY KEY, 
      `title` varchar(200), 
      `body` text, 
      `author` varchar(100), 
      `last_moderator` varchar(100), 
      `category` int(10), 
      `cdate` datetime, 
      `lmdate` datetime, 
      `commentable` boolean, 
      `active` boolean) CHARACTER SET utf8 COLLATE utf8_bin 
       "; 

下面是查詢。正如你所看到的，我需要id作爲主鍵，但是這個查詢結果有兩個主鍵：id和body。人們幫助我 - 我冥想了20分鐘的查詢，但我沒有看到任何錯誤。

Answer 1

呃，不，它不.... body沒有被定義爲一個關鍵，主要或以其他方式：

mysql> CREATE TABLE IF NOT EXISTS `myTable` (
    ->    `id` int unsigned UNIQUE NOT NULL AUTO_INCREMENT PRIMARY KEY, 
    ->    `title` varchar(200), 
    ->    `body` text, 
    ->    `author` varchar(100), 
    ->    `last_moderator` varchar(100), 
    ->    `category` int(10), 
    ->    `cdate` datetime, 
    ->    `lmdate` datetime, 
    ->    `commentable` boolean, 
    ->    `active` boolean) CHARACTER SET utf8 COLLATE utf8_bin; 
Query OK, 0 rows affected (0.02 sec) 

mysql> show indexes from myTable; 
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ 
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | 
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ 
| myTable |   0 | PRIMARY |   1 | id   | A   |   0 |  NULL | NULL |  | BTREE  |   |    | 
| myTable |   0 | id  |   1 | id   | A   |   0 |  NULL | NULL |  | BTREE  |   |    | 
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ 
2 rows in set (0.00 sec)