Mysql表键

Question

谁能告诉我 KEY fk_pickup_method (pickup_method_id) 是什么意思， 关键 fk_deliv_method (delivery_method_id) 行。因为 pickup_method 和 deliv_method 不是表。那么这些线有什么用。

CREATE TABLE `test` (
`idTest` int(11) NOT NULL AUTO_INCREMENT,
`Name` mediumtext NOT NULL,
`email` varchar(45) NOT NULL,
`password` varchar(45) NOT NULL,
`firstname` varchar(45) NOT NULL,
`lastname` varchar(45) NOT NULL,
`phone` bigint(20) unsigned NOT NULL,
`address_street` varchar(128) NOT NULL,
`address_apt` varchar(45) DEFAULT NULL,
`address_city` varchar(128) NOT NULL,
`address_state` varchar(2) NOT NULL,
`address_zip` int(11) NOT NULL,
`fax` bigint(20) unsigned DEFAULT NULL,
`account_balance` float NOT NULL DEFAULT '0',
`delivery_radius` float DEFAULT NULL,
`pickup_method_id` int(11) NOT NULL DEFAULT '0',
`delivery_method_id` int(11) NOT NULL,
`is_deleted` tinyint(1) NOT NULL DEFAULT '0',
`lat` float NOT NULL DEFAULT '0',
`lng` float NOT NULL DEFAULT '0',
`timezone` varchar(45) NOT NULL,
PRIMARY KEY (`idTest`),
UNIQUE KEY `phone_UNIQUE` (`phone`),
KEY `fk_pickup_method` (`pickup_method_id`),
KEY `fk_deliv_method` (`delivery_method_id`)
) 

Answer 1

它们是 () 中列的索引。但这些字段并不局限于唯一。

在此 MySQL document link 中查找 {INDEX|KEY} .