MySQL：密钥 2 的重复条目
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MySQL: Duplicate Entry for Key 2
提问by Nick Heiner
I'm not sure what I'm doing to cause this error. The query:
我不确定我在做什么导致这个错误。查询：
INSERT INTO node (type, language, title) VALUES ('bout', 'en', 'the title 3')
The error:
错误：
#1062 - Duplicate entry '0' for key 2
The table:
桌子：
CREATE TABLE `node` (
`nid` int(10) unsigned NOT NULL auto_increment,
`vid` int(10) unsigned NOT NULL default '0',
`type` varchar(32) NOT NULL default '',
`language` varchar(12) NOT NULL default '',
`title` varchar(255) NOT NULL default '',
`uid` int(11) NOT NULL default '0',
`status` int(11) NOT NULL default '1',
`created` int(11) NOT NULL default '0',
`changed` int(11) NOT NULL default '0',
`comment` int(11) NOT NULL default '0',
`promote` int(11) NOT NULL default '0',
`moderate` int(11) NOT NULL default '0',
`sticky` int(11) NOT NULL default '0',
`tnid` int(10) unsigned NOT NULL default '0',
`translate` int(11) NOT NULL default '0',
PRIMARY KEY (`nid`),
UNIQUE KEY `vid` (`vid`),
KEY `node_changed` (`changed`),
KEY `node_created` (`created`),
KEY `node_moderate` (`moderate`),
KEY `node_promote_status` (`promote`,`status`),
KEY `node_status_type` (`status`,`type`,`nid`),
KEY `node_title_type` (`title`,`type`(4)),
KEY `node_type` (`type`(4)),
KEY `uid` (`uid`),
KEY `tnid` (`tnid`),
KEY `translate` (`translate`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=2586 ;
What am I doing wrong? By not specifying a nid for the new entry, it will auto-increment, right?
我究竟做错了什么？通过不为新条目指定 nid，它将自动递增，对吗？
回答by Mike
You have vidas a unique key. However you never set a value for it so the default 0 is always used. Second entry into the table will violate uniqueness.
你有vid一个唯一的键。但是，您从未为其设置值，因此始终使用默认值 0。第二次进入表将违反唯一性。
回答by Max Shawabkeh
The problem looks to be with vidnot being specified. The first entry you put will have had a vidof 0 (the default) and the next will try 0 again and fail on the UNIQUEindex. Not that only the primary key, nid, will auto-increment.
问题似乎是vid没有被指定。您放置的第一个条目vid的值为 0（默认值），下一个将再次尝试 0 并在UNIQUE索引上失败。不仅是主键nid, 会自动递增。
回答by Dave Sims
I think nid isn't the problem, vid is. It defaults to 0 and is designated unique.
我认为 nid 不是问题，vid 是。它默认为 0 并被指定为唯一的。
