Grails GORM, robust fetch mode for multiple layers of a domain class

Question

I have the following domain structure:

class Survey { Integer id String title static hasMany = [questions: Question] static constraints = { id() title() questions() } String toString(){ return title } } class Question { Integer id String text static hasMany = [responses: Response] static fetchMode = [responses: 'eager'] static constraints = { id() text() responses() } String toString(){ return text } } class Response { Integer id String text Integer numberOfPeopleSelected = 0 static constraints = { id() text() numberOfPeopleSelected() } String toString(){ return text } } 

I modified Bootstrap.groovy to initialize some data at startup, and separate calls to Survey.list() , Question.list() and Response.list() show that each individual level is created with the expected values

However, when I do Survey.list() and deal with questions, the answers are always null:

I expected that by setting fetchMode it should always load this particular object.

What can I change on my domain objects to make sure that when I do something like Survey.findById(1) , it downloads all the questions and answers?

thanks

Answer 1

please define it in your class Survey

 static fetchMode = [questions: 'eager'] 

if this does not work as fetchMode 'eager' is deprecated

you can also try

 static mapping = { questions fetch :'join' } 

follow this to learn more about the selection strategy https://grails.imtqy.com/grails-doc/3.0.x/ref/Database%20Mapping/fetch.html