grails - pertenece a dominio múltiple

gorm grails-plugin

Question

Tengo 4 clases, incidentes, problemas, solicitudes y otro es Adjunto.

Cada dominio se parece a .........

    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
}

cuando estoy guardando el objeto del incidente, arroja una excepción como Columna ''problema_id'' no puede ser nulo. ¿qué hacer?

Answer 1

Intenta eliminar los incidentes, problemas y solicitudes de HasOne en clase y reemplázalo con

   Attachment attachment
   static constraints = {attachment: unique: true, nullable:true}       
   static mapping = {
    attachment  cascade: "delete"
    }