Grails Map域类的列名问题

Question

I have a MS SQL DB (which I can't change) with 3 tables :

contact  
id, name, number

c_group  
id,name,email

contact_group  
id, contact_id, group_id  

In Grails I have 3 domain classes :

class Cgroup {  
    String name
    String email

    static constraints = {
    }

    static mapping = {
        table name: "c_group"
        version false
    }   
}

class Contact {
    String name
    String number

    static constraints = {
        name nullable:false
    }

    static mapping = {
        version false
    }
}

class Contact_group {
    Cgroup cgroup
    Contact contact

    static constraints = {
    }

    static mapping = {
        version false
        cgroup_id column: "c_group_id", sqlType: "int" 
    }
}

I'm trying to create a list using :-

def contactInstance = Contact.get(id)  //I have previously got the id

List userGroupList = Contact_group.createCriteria().list(params) {            
    eq("contact", contactInstance)
}

And it is throwing an error

Invalid column name 'cgroup_id'.. Stacktrace follows:

As you can see, I'm trying to map the correct column name (in the Contact_group domain class) as the table has been renamed from group to c_group in the DB, and just to complicate matters for some reason I decided to call the domain class Cgroup in my Grails app. (I can change this if needs be)

So, I'm now in a bit of a muddle about how best to create the list. Any suggestions or pointers?

Answer 1

In your mapping you should point to the class property ( cgroup_id should be cgroup , since that is what you named it in your domain.)

Also, your column name in your table is id not c_group_id so you should set the column as id .

static mapping = {
    version false
    table name: "contact_group"
    cgroup column: "id", sqlType: "int"        
}