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POProblem with duplicates using Grails' withCriteria function with a many-to-many relationship
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copied!<p>I've got 2 tables, Question and Answer, with a many-to-many relationship (i.e. Questions can have multiple Answers and Answers can be reused by multiple Questions). For normalization, I have a cross-reference table between them named Question_Answer that has a many-to-one relationship with both tables. These are their class definitions:</p> <pre><code>class Question { int id int text static hasMany = [questionAnswers : QuestionAnswer] } class Answer { int id int text static hasMany = [questionAnswers : QuestionAnswer] } class QuestionAnswer { int id Question question Answer answer } </code></pre> <p>I'm trying to get a list of Answers based on certain criteria. Here is my criteria query (using Grails' <code>withCriteria</code> function):</p> <pre><code>def listing = Answer.withCriteria { cache false order "id", "asc" eq("id", myAnswerID) questionAnswers { question { isNotNull("text") } } } </code></pre> <p>Here's an example of the problem I'm having:</p> <p>I have an Answer that matches 3 different Questions. What I want in the "listing" is 1 <code>Answer</code> object, with its <code>questionAnswers</code> list populated with the 3 matching <code>QuestionAnswer</code> objects. Instead, I'm getting 3 identical <code>Answer</code> objects, all with their <code>questionAnswers</code> lists populated.</p> <p>Is there a simple way to achieve what I want? I'm hoping I'm just missing something small.</p> <p>Any help/suggestions are much appreciated.</p> <p>Thanks, B.J.</p>

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