使用executeUpdate()删除 - grails

Question

我现在遇到问题,我有2个域类,即医生和病人,他们有1:m的关系.这是我的班级医生的代码

class Doctor {

String name
String specialization

def doctorService

static hasMany = [patients: Patient]
static belongsTo = [hospital: Hospital]


static constraints = {

    name(blank:false)
    specialization(blank:false)
    patients(nullable:true)
    hospital(nullable:false)
}

String toString(){

    "Doctor ${name} "

}

}

- >这是我的类患者代码:

class Patient {

String name
String ailment
int age
Date dateAdmit, dateDischarge

static belongsTo = [doctor: Doctor, hospital: Hospital]

static constraints = {

    name(blank:false, maxSize:100)
    ailment(blank:false)
    age(size:1..200)
    dateAdmit(nullable:true)
    dateDischarge(nullable:true)
    hospital(nullable:false)
    doctor(nullable:false, validator:{val, obj -> val.hospital == obj.hospital})

}

String toString(){

    "${name} "

}
}

- >我想删除一个医生谁没有一个病人使用的executeUpdate() .我可以选择没有患者的医生使用这样的动态查找器. _

def d = Doctor.findAll("from Doctor as d where not exists" +
    "(from Patient as p where p.doctor = d)")

_

似乎该语法在executeUpdate()中不起作用,我只是grails中的新手.请帮帮我..谢谢......

Answer 1

用这个:

Doctor.executeUpdate('delete from Doctor d where d.patients is empty')