附录
class User {
static hasMany = [books:Book]
}
class Book {
static belongsTo = [user:User]
}
戈尔姆为图书表增加了用户栏和外国钥匙。 我如何能够在这一栏中增加一个指数?
附录
class User {
static hasMany = [books:Book]
}
class Book {
static belongsTo = [user:User]
}
戈尔姆为图书表增加了用户栏和外国钥匙。 我如何能够在这一栏中增加一个指数?
这似乎是最简单的运作方式。 你们不需要具体说明外国钥匙或其他东西。
class Book {
static belongsTo = [user:User]
static mapping = {
user index: index_book_user_id
}
}
我不敢肯定,Grails允许你在缺席的情况下这样做。 你可以具体指出,铁路公司使用某一栏表中的现有指数,但我认为,在铁路公司违约后指数的栏目中,需要人工制作索引。
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