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标题: 在导出的DDL中key为何意？ [打印本页]

作者: ayalastrike 时间: 2008-08-20 10:36
标题: 在导出的DDL中key为何意？
CREATE TABLE `customer_news_letter` (
  `customer_news_letter_id` int(11) NOT NULL,
  `customer_id` int(11) NOT NULL,
  `news_letter_schedule_id` int(11) NOT NULL,
  `subscribe_date` datetime NOT NULL,
  `unsubscribe_date` datetime default NULL,
  `send_format_type_id` int(11) default NULL,
  PRIMARY KEY  (`customer_news_letter_id`),
  KEY `FK_customer_news_letter_type_id` (`send_format_type_id`),
  KEY `FK_customer_news_letter_schedule_id` (`news_letter_schedule_id`),
  KEY `customer_id` (`customer_id`),
  KEY `subscribe_date_index` (`subscribe_date`),
  KEY `unsubscribe_date_index` (`unsubscribe_date`),
  CONSTRAINT `FK_customer_news_letter_1_1` FOREIGN KEY (`news_letter_schedule_id`) REFERENCES `news_letter_schedule` (`news_letter_schedule_id`),
  CONSTRAINT `FK_customer_news_letter_type_id` FOREIGN KEY (`send_format_type_id`) REFERENCES `types` (`type_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

这个里面我知道PK是customer_news_letter_id
FK是news_letter_schedule_id和send_format_type_id
但是里面的这些KEY是什么呢？
  KEY `FK_customer_news_letter_type_id` (`send_format_type_id`),
  KEY `FK_customer_news_letter_schedule_id` (`news_letter_schedule_id`),
  KEY `customer_id` (`customer_id`),
  KEY `subscribe_date_index` (`subscribe_date`),
  KEY `unsubscribe_date_index` (`unsubscribe_date`),

作者: realzyy 时间: 2008-08-20 14:36
key就是索引

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