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POhibernate join fetch does not fetch all children
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copied!<p>I'm using the play framework and JPA and Hibernate.</p> <p>I have several entities :</p> <pre><code>@Entity public class Player extends Model { public enum Gender { MALE, FEMALE } @Required public String name; @Required public Gender gender; @Required public Long gold; } @Entity public class Building extends Model { @Required @ManyToOne(fetch = FetchType.LAZY) public Player owner; @Required public String buildingType; @Required public Long buildingId; } @Entity public class Stock extends Model { // Either a product type or a raw material @Required public Long goodId; @Required public Boolean isProduct; @Required public String image; } @Entity public class Contract extends Model { @Required @ManyToOne(fetch = FetchType.LAZY) public Player player; @Required @ManyToOne(fetch = FetchType.LAZY) public Building building; @Required @ManyToOne(fetch = FetchType.LAZY) public Stock stock; @Required public Long ordersLeft; @Required public Long cyclesLeft; } </code></pre> <p>With these entities I would like to retrieve all my <code>Contract</code> and their associated <code>Building</code>, <code>Stock</code> and <code>Player</code></p> <p>Here is the query I' using :</p> <pre><code>public static List<Contract> retrieveContractsForNewOrder() { return find("select distinct c from Contract c " + "left join fetch c.player " + "left join fetch c.stock " + "left join fetch c.building " + "where c.cyclesLeft = 0 and c.ordersLeft > 0").fetch(); } </code></pre> <p>The query is working, I retrieve my list of <code>Contract</code>. However, the <code>building</code> and <code>stock</code> variables are loaded but the <code>player</code> variable is not (The class name in the <code>Contract</code> object is <code>Player_$$_javassist_22</code> and it has a handler named <code>JavassistLazyInitializer</code>).</p> <p>I don't know what I'm doing wrong and why Hibernate refuses to fetch the player model while it's fetching the other models ...</p> <p>Thank you for your help</p> <p><strong>EDIT</strong></p> <p>After some tests the query executed by hibernate seems correct : all joins are there and all fields from all models are in the select.</p> <p>However the results are strange : I'm only retrieving fields from <code>Contract</code> and <code>Stock</code> (not from <code>Building</code> and <code>Player</code>).</p> <p>But my <code>Building</code> is loaded, why ? Because of the cache ? And why <code>Building</code> and <code>Player</code> does not appear in results ?</p> <p><strong>EDIT 2</strong></p> <p>I tried to execute the exact same request directly in MySQL and I'm retrieve all the variables I need, while Hibernate seems to skip some variables (they are not all in the results).</p> <p>What's happening ?</p> <p><strong>EDIT 3</strong></p> <p>I tried to <code>clear()</code> the session cache before doing my query and guess what ? The <code>Player</code> is loaded ...</p> <p>I tried to only load the <code>Player</code> using the <code>left join fetch</code> but it was still not working (but <code>Building</code> was loaded thanks to the cache). <code>Player's</code> fields were not in the results. However, as soon as I cleared the cache the <code>Player's</code> fields appeared in the results and the <code>Player</code> is loaded in my <code>Contract</code>.</p> <p>Why clearing the cache solved the issue? <code>Player</code> was in the cache ? If so, why wasn't it loaded? I don't understand what happens, but I can't just clear the cache as I need to make a lot of other queries after this one and I need the cache for them.</p>

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