Grails GORM多对多关系
当其父Grails GORM多对多关系,grails,groovy,orm,gorm,Grails,Groovy,Orm,Gorm,当其父用户被删除时，我想删除所有的推文，当其父推文被删除时，我还想删除协作者。其中合作者如果属于用户 目前，Tweet视图没有连接协作者。我在想，如果我做对了以下几点： Tweet.groovy User owner static hasMany = [ collaborators : User ] static belongsTo = User static hasMany = [ tweet : Tweet ] static hasMany = [ collaborators : Us
用户推文推文合作者用户User owner
static hasMany = [ collaborators : User ]
static belongsTo = User
static hasMany = [ tweet : Tweet ]
static hasMany = [ collaborators : User ]
static belongsTo = User
User createdBy
static mappedBy = [collaborators : 'tweet']
static hasMany = [ tweet : Tweet ]
static mappedBy = [tweet : 'collaborators']
User owner
static hasMany = [ collaborators : User ]
static belongsTo = User
static hasMany = [ tweet : Tweet ]
static hasMany = [ collaborators : User ]
static belongsTo = User
User createdBy
static mappedBy = [collaborators : 'tweet']
static hasMany = [ tweet : Tweet ]
static mappedBy = [tweet : 'collaborators']
在我看来，你缺少一种关系，即推特是由特定用户拥有的。现在你只会得到一个多对多的关系，我猜你不想在删除一个用户时删除所有用户合作的推文 Tweet.groovy
User owner
static hasMany = [ collaborators : User ]
static belongsTo = User
static hasMany = [ tweet : Tweet ]
static hasMany = [ collaborators : User ]
static belongsTo = User
User createdBy
static mappedBy = [collaborators : 'tweet']
static hasMany = [ tweet : Tweet ]
static mappedBy = [tweet : 'collaborators']
User owner
static hasMany = [ collaborators : User ]
static belongsTo = User
static hasMany = [ tweet : Tweet ]
static hasMany = [ collaborators : User ]
static belongsTo = User
User createdBy
static mappedBy = [collaborators : 'tweet']
static hasMany = [ tweet : Tweet ]
static mappedBy = [tweet : 'collaborators']
上面的mappedBy是必需的，因为类之间有两种关系，Grails需要知道多对多使用哪种关系。错误：在多对多关系中的域类[class com.brewee.User]和[class com.brewee.Tweet]之间没有定义所有者。示例：static belongsTo=com.brewee.tweet接受的答案是正确的语法，但解决方案是相同的。选择公认的答案。我将编辑我的回复，使其正确无误，以免混淆任何人。正在尝试