我有一个名为@mixin dynamic-bg($path, $type, $ext, $source-list) {
@each $source in $source-list {
&[data-bg="#{$source}"] {
background: url($path + $source + '_' + $type + '.' + $ext) no-repeat;
}
}
}
a {
@include dynamic-bg($path, "logo", "png", ("alpha", "beta", "gamma"));
}
strong {
@include dynamic-bg($path, "logo", "png", ("strong-1", "strong-2"));
}
的表格：
participants创建参与者的规则是每个注册的电子邮件地址只能参加一个锦标赛（外键CREATE TABLE IF NOT EXISTS `participants` (
`id` int(8) NOT NULL AUTO_INCREMENT,
`email` varchar(30) NOT NULL,
`name` varchar(40) NOT NULL,
`birthdate` date NOT NULL,
`personal_number` varchar(16) DEFAULT NULL,
`phone` varchar(16) NOT NULL,
`photo` varchar(100) NOT NULL,
`address` text NOT NULL,
`city_id` int(3) DEFAULT NULL,
`tournament_id` int(8) NOT NULL,
`time_created` datetime NOT NULL,
`time_modified` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`),
KEY `city_id` (`city_id`),
KEY `tournament_id` (`tournament_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
）;因此两个记录具有相同的电子邮件地址但不同的 tournament_id应允许。
tournament_id表单验证是否能够执行此操作？或者我应该创建一个回调或帮助？
答案 0 :(得分：1)
is_unique只是value_does_not_already_exists_in_a_single_column的简称。
所以，不，它不会胜任这项工作;你需要回电。