近期项目中需要 关联 几张表再把字段转出来,在这里记录以下,我感觉网上写的都不太规范和清晰。
@Entity@SqlResultSetMapping( name="TestMapping", entities = { @EntityResult( entityClass = com.xxx.xx.data.model.TestEntity.class, fields = { @FieldResult(name="id",column="id"), @FieldResult(name="localTime",column="time"), @FieldResult(name="maximumAppointment",column="maxAppointment"), } ) })@NamedNativeQuery(name="getTestQuery", query="select tableC.id as id,tableB.time,tableC.maximumAppointment as maxAppointment from tableB " + " inner join tableA on tableA.id = tableB.tableAId " + " inner join tableC on tableB.id = tableC.tableBId " + " inner join custom on custom.id = tableA.customId " + "where " + " tableA.locationId = :locationId" + " and custom.id = :customId" + " and tableB.deleted = false ", resultSetMapping="TestMapping")@Datapublic class TestEntity { @Id private String id; private LocalTime localTime; private Integer maximumAppointment;}需要声明接口:
若不想声明接口,那可以用EntityManager 来实现。
CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。