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POJPA query for given task
 

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    <p>I am working on some academic task and I'm stuck. The situation is as follows:<br> I have three simple database tables and Java @Entity classes generated from them.</p> <p>Table Mark:<br> STUDENT_ID (PK)<br> SUBJECT_ID (PK)<br> MARK<br></p> <pre><code>public class Mark implements Serializable { private BigDecimal mark; @Id @Column(name = "STUDENT_ID", nullable = false, insertable = false, updatable = false) private BigDecimal studentId; @Id @Column(name = "SUBJECT_ID", nullable = false, insertable = false, updatable = false) private BigDecimal subjectId; @ManyToOne @JoinColumn(name = "SUBJECT_ID") private Subject subject; @ManyToOne @JoinColumn(name = "STUDENT_ID") private Student student; (...) } </code></pre> <p>Table Student:<br> INDEX_NO (PK)<br> FNAME<br> LNAME<br> FACULTY_ID<br></p> <pre><code>public class Student implements Serializable { @Column(name = "FACULTY_ID", nullable = false) private BigDecimal facultyId; @Column(nullable = false, length = 20) private String fname; @Id @Column(name = "INDEX_NO", nullable = false) private BigDecimal indexNo; @Column(nullable = false, length = 20) private String lname; @OneToMany(mappedBy = "student") private List&lt;Mark&gt; marksList1; (...) } </code></pre> <p>Table Student:<br> ID (PK)<br> NAME<br></p> <pre><code>public class Subject implements Serializable { @Id @Column(nullable = false) private BigDecimal id; @Column(nullable = false, length = 60) private String name; @OneToMany(mappedBy = "subject") private List&lt;Mark&gt; marksList; (...) } </code></pre> <p>The task is to obtain two lists:<br> 1. The list of students which does not have marks from all of the subjects yet.<br> 2. The list of subjects from which particular student does not have a mark.<br></p> <p>I am not too good at SQL, so I have problem with query construction. It can be solved by any JPA-like way, i.e. JPQL, Criteria API.</p> <p>So I am asking you for a help.<br> Thank you for your interest.</p>
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