Grails如何与SQL Server数据库正确地一对多映射

Question

I have two domain classes and the relationship between them is 1 to Many. I know how to map the columns of each class to their respective tables individually but how do I map the relationship that exists in my MSSQL database? There is no join table and I only have read-only access. I've looked at various pages of the Grails documentation and this is where I am at at the moment (One student has many courses). In my tables the foreign key that ties the two tables together is in the Courses table.

class StudentHeader { //on the one side
    String stuNo
    String stuName
    String stuStreet

    static mappedBy = [refs: "fkCustNo"]

    static hasMany = [refs: CourseHeader]
    static constraints = {
    }

    static mapping = {
        table name: "[tbl_Students]", schema: "[dbo]", catalog: "[CRD].[CourseTrak]"
        version false
        id generator: 'assigned', name: 'stuNo'
        stuNo column: '[PK_StudentNo]'
        stuName column: '[Student_Name]'
        stuStreet column: '[Student_Street]'


    }
}

class CourseHeader { //on the many side
    String courId
    String courName
    StudentHeader fkCourNo
    static constraints = {
    }

    static mapping = {
        table name: "[tbl_Courses]", schema: "[dbo]", catalog: "[CRD].[CourseTrak]"
        version false
        id generator: 'assigned', name: 'courId'
        courId column: '[PK_CourseId]'
        courName column: '[Course_Name]'
        fkCourNo column: '[FK_CourseNo]'


    }
}

As a test here is how I am trying to access the courses of a student

StudentHeader.first().refs

Answer 1

I believe I have it figured out. For the domain class on the many side you need to set insert and updateable equal to false like so (The object field in your "many" domain has to have the same value as the key-value pair in mappedBy):

class StudentHeader{
static mappedBy = [refs: "fkCustNo"]
}

class CourseHeader { //on the many side
    String courId
    String courName
    StudentHeader fkCustNo
    static constraints = {
    }

    static mapping = {
        table name: "[tbl_Courses]", schema: "[dbo]", catalog: "[CRD].[CourseTrak]"
        version false
        id generator: 'assigned', name: 'courId'
        courId column: '[PK_CourseId]'
        courName column: '[Course_Name]'
        fkCustNo column: '[FK_CourseNo]', insertable: false, updateable: false


    }
}