我有 4 个类(class)、事件、问题、请求,另一个是附件。
每个域看起来都像......
Class Incidents
{
// other fields
static hasOne = [attachment: Attachment]
static constraints = [attachment nullable:true]
}
Class Problems
{
// other fields
static hasOne = [attachment: Attachment]
static constraints = [attachment nullable:true]
}
Class Requests
{
// other fields
static hasOne = [attachment: Attachment]
static constraints = [attachment nullable:true]
}
Class Attachment
{
// other fields
static belongsTo= [
incident: Incidents,
problem: Problems,
requests: Requests
]
static constraints = {
incident nullable: true
problem nullable: true
requests nullable: true
}
当我保存事件对象时,它会抛出异常,例如列“problem_id”不能为空。 该怎么办?
最佳答案
尝试删除类事件、问题、请求上的 hasOne 并将其替换为
Attachment attachment
static constraints = {attachment: unique: true, nullable:true}
static mapping = {
attachment cascade: "delete"
}
关于grails - 属于多个域,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/11077871/