StackOverflow2013

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18581647
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2013-09-02T22:36:42.583
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2013-09-02T22:36:42.583
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text
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The way to do this is to define two @Embeddable entities to represent the composite keys for A and B. BKey is identical to AKey except that it adds "a6" property. AKey Class: <pre><code>@Embeddable public class AKey implements Serializable { private String a1; private String a2; private String a3; private String a4; private String a5; public AKey() { } public AKey(String a1, String a2, String a3, String a4, String a5) { this.a1 = a1; this.a2 = a2; this.a3 = a3; this.a4 = a4; this.a5 = a5; } ... // getters & setters } </code></pre> Then you define your A class to use the Embeddable composite key class as the @IdClass but still use the composite key elements as properties. You would do the same thing for the B class (using BKey). Define the @OneToMany mapping in A for the "Set bs" property with the required @JoinColumns. <pre><code>@Entity @IdClass(AKey.class) public class A { @Id private String a1; private String a2; private String a3; private String a4; private String a5; @OneToMany(targetEntity=B.class, cascade={CascadeType.ALL}) @JoinColumns({@JoinColumn(name="a1"), @JoinColumn(name="a2"), @JoinColumn(name="a3"), @JoinColumn(name="a4"), @JoinColumn(name="a5")}) private Set bs = new HashSet(); public A() { } public A(AKey id, String prop1) { this.a1 = id.getA1(); this.a2 = id.getA2(); this.a3 = id.getA3(); this.a4 = id.getA4(); this.a5 = id.getA5(); this.prop1 = prop1; } public Set getBs() { return bs; } public void setBs(Set bs) { this.bs = bs; } ... // getters & setters and anything else in A } </code></pre> I didn't have any issues with this approach - it expected the table structure you defined (A with a 5-column primary key, B with a 6-column primary key and a 5-column foreign key to A). The following test case correctly created an A with 2 associated Bs that could be retrieved using JQL. <pre><code>B b = new B(new BKey("a", "b", "c", "d", "e", "1"), "prop1"); B b2 = new B(new BKey("a", "b", "c", "d", "e", "2"), "prop1"); A a = new A(new AKey("a", "b", "c", "d", "e"), "prop1"); a.getBs().add(b); a.getBs().add(b2); manager.persist(a); .... </code></pre> Hope this helps. Sarah
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Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POOne to Many relationship between two Entities when both entities has composite primary key
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 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. This table or related slice is empty.
UserOwnerUserId
1. USSarah
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