java - 使用 hibernate 条件获取具有不同的 id

Question

我想获取具有不同批处理代码和 ID 的行。

下面的代码现在正在获取重复的批处理代码，例如:

batch1 12,
batch1 45,
batch1 63,
batch2 96,
batch2 96

@Entity
@Table(name = "key")
public class Key implements Serializable {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", nullable = false, length = 11)
    @Column(name = "batch_code", nullable = false)
    private String batchCode;

    //getter , setter
}



Criteria c = getSession().createCriteria(Key.class);

ProjectionList projList = Projections.projectionList();
projList.add(Projections.property("batchCode"));

c.setProjection(Projections.distinct(projList));
c.setProjection(Projections.property("id"));

if (searchTerm != null && !searchTerm.isEmpty()) {
    c.add(Restrictions.like("keyCode", searchTerm.toUpperCase() + "%"));
}

c.setFirstResult(currPosition);
c.setMaxResults(pageSize);

List<Key> result = c. list();

Answer 1

您似乎在条件中设置了多个预测。最后一个覆盖前面的一个。为避免这种情况，您可以使用 ProjectionList 添加多个投影，如下所示

    Criteria c = getSession().createCriteria(Key.class);
    ProjectionList projList = Projections.projectionList();
    projList.add(Projections.distinct(Projections.property("batchCode")));
    projList.add(Projections.property("id"));
    c.setProjection(projList);
      if (searchTerm != null && !searchTerm.isEmpty()) {
          c.add(Restrictions.like("keyCode", searchTerm.toUpperCase() + "%"));
      }
    c.setFirstResult(currPosition);
    c.setMaxResults(pageSize);
    List<Key> result = c. list();